Rolex Oyster – 90 Years of Perpetual Innovation

In 2016, Rolex celebrated 90 years of the Oyster, the first waterproof and dust-proof wristwatch in the world. Created in 1926, the Rolex Oyster was a landmark in watchmaking that brought fundamental improvements to the reliability and precision of the wristwatch.

It was an innovation that transformed watch design forever. Precise, robust and reliable, the Oyster became the timekeeper of choice for explorers and pioneers of all types whose exploits played a part in forging the status of this legendary watch. Today, Rolex has further reinforced the performance criteria that qualify Oyster watches as Superlative Chronometers.

“Gentlemen, we make the best wristwatch in the world.” In January 1927, the founder of Rolex addressed an assembly of watch retailers to present his most recent creation: the Rolex Oyster. It had been launched a few months earlier, in 1926, and was the first-ever completely hermetic and waterproof wristwatch.


And Hans Wilsdorf was a man to be believed. In little more than 20 years, he had founded and established a pioneering wristwatch brand renowned for its spectacular advances in precision and original designs. He could legitimately proclaim that he had created by that time “more successful models of wristwatches for the British market than the whole of Switzerland combined”.

Hans Wilsdorf had made precision his top priority. In 1910, a Rolex was the very first wristwatch to obtain a chronometer certificate – an official mark of precision. Granted by an official watch rating centre in Switzerland, it showed for the first time that a wristwatch could be as precise as a pocket watch, the benchmark in those days. In 1914, the Kew Observatory in Great Britain – the highest authority for chronometric precision at the time – awarded a “Class A” precision certificate to a Rolex wristwatch.


This was a certification that involved extremely rigorous tests lasting 45 days and had generally been reserved for large marine chronometers. Rolex had now proved that a wristwatch could rival the most precise of timepieces – a fact scarcely believable at the time. Such success for Rolex contributed significantly to establishing the credibility of this type of watch. Until then wristwatches had been considered jewellery items of particular appeal to women and lacking in precision.

In a document written to celebrate the 40th anniversary of Rolex in 1945, Hans Wilsdorf spoke about the doubts that had beset watchmakers back in that era: “Watchmakers all over the world remained skeptical as to [the wristwatch’s] possibilities and believed that this new-fangled object was bound to prove a failure. Their arguments against the wristwatch were, inter alia, the following: firstly, the mechanism required by this type of watch must of necessity be small and delicate and it could never withstand the violent gestures of hand and arm. Secondly, dust and damp would rapidly spoil the mechanism, even if it were well constructed. Thirdly, accuracy and regularity of working could never be obtained with so small a movement.”

Hans Wilsdorf 
Hans Wilsdorf 

After conquering precision, Hans Wilsdorf turned his attention to overcoming the other two challenges. “To my technical assistants, my constant refrain from the earliest days was: ‘We must succeed in making a watch case so tight that our movements will be permanently guaranteed against damage caused by dust, perspiration, water, heat and cold. Only then will the perfect accuracy of the Rolex watch be secured,’” he explained.

The introduction of the Oyster marked a second fundamental milestone in the realization of Hans Wilsdorf’s vision. The Oyster offered, he said, “the ideal solution [to] a problem that has baffled everybody since watches [have been] worn on the wrist”. And he continued: “I prophesy that the Oyster will popularize the wearing of wristwatches with men more than anything else has done.” With the Oyster, Hans Wilsdorf explained, it was no longer necessary to remove the watch to wash one’s hands or bathe, or while at work in a dusty workshop or when perspiring profusely. “You just keep your Oyster on your wrist whatever happens and it will never fail you.” A time-honoured promise that would lead to the Oyster’s being chosen and relied on by numerous pioneers – from climbers of the highest peaks to explorers of the deepest reaches of the oceans.

The hermetically sealed Oyster provided optimal protection for the movement, thanks to an ingenious case with a patented system of a screw-down bezel, case back and winding crown. It was a total watchmaking concept. Case and movement were considered as one in the overall goal of improving chronometric performance. If Hans Wilsdorf presented the Oyster as such an important invention, it was down to the fact that its waterproofness also contributed greatly to maintaining precision over the long-term.

As the founder of Rolex explained at length in 1927: “Apart from being waterproof, dirt and every other proof [the Oyster] has the very important advantage over all other watches [in] that it will maintain its time keeping and not…vary gradually, more and more, for the simple reason that the true cause of such irregularities is banned. We all know that the pivots must run in oil, and oil attracts all those fine particles of dust, which constantly, although in only very small quantities, penetrate into all watch movements, however well the cases are made. The rotary action of the pivots gradually makes a paste of the oil that thickens more as time goes on, and dust gets attracted and is mixed up with it. This paste acts like emery paper on the very fine pivots and pinions and gradually they get worn away, very little of course, but sufficiently to cause bad time keeping. […] Our Oyster excludes all dust and consequently it will always maintain perfect time.”


 The Oyster had yet a third advantage. Hans Wilsdorf appreciated the importance of aesthetics for a wristwatch, which is much more conspicuous than a pocket watch: “Once and for ever the problem of having a hermetically sealed watch is solved – and solved in such a way that beauty of design goes hand-in-hand with utility.”

Why did Hans Wilsdorf decide to call his waterproof watch the Oyster? Here is an explanation he gave in 1945: “The fact that, like an oyster, it can remain an unlimited time under water without detriment to its parts, gave me the idea of christening it the ‘Rolex Oyster’, the name under which it has become famous throughout the world.”

He was even more explicit in the 1927 speech in describing the newly invented Oyster as “a model housekeeper” that “simply tolerates no dust or other impurities. […] Gentlemen, we have borrowed these qualities and also her name. Here is a specimen of the Rolex Oyster – so called because it lives in water and shuts out all impurities”.

The Rolex Oyster was one of the most important watchmaking inventions of its time and, in 1945, talking about the 1926 era Hans Wilsdorf said: “In those days, the idea of a watch impermeable to water appeared quite utopian and without future to the majority of manufacturers and technicians who did not, in fact, see its necessity or utility. At trade congresses and meetings, the ‘waterproof’ watch was held to scorn by specialists and a discussion of the problem provoked sarcasm rather than useful and objective arguments.”

However, Mr Wilsdorf persevered and, through a communications drive, made the watch known and appreciated all over the world. “Other manufacturers had to follow the movement which was to exercise an enormous influence on the entire Swiss watchmaking industry… Statistics show that since 1927 waterproof wristwatches, to a value of more than one thousand million Swiss francs, have been exported throughout the five continents. Another and no less tangible result of the development of the waterproof watch is the profound modification it has brought to the manufacture of watch cases generally in Switzerland. Old machinery, incapable of turning out such delicate work, had to be replaced by new and more accurate machines. Millions of francs were invested in this modern technique and the machine industry entered a new era of prosperity. The Swiss watch-case industry itself regained its position as the first in the world and this at a time when it seemed to have most serious foreign competition to face.”

As protected as it was in its waterproof case, the original Oyster still had one flaw in its armour: like all watches of its day, it needed to be wound regularly to supply the energy necessary for it to work. This meant unscrewing its waterproof winding crown, thereby breaching the barrier between the exterior and the interior of the watch, and allowing humidity and impurities to penetrate.

To complete the Oyster concept and ensure a truly hermetic environment for the movement, a way had to be found to avoid this and for the movement to rewind itself without the help of outside energy. Self-winding had already been brought into pocket watches by eminent watchmakers in the 18th century.

In the 1920s its use spread to wristwatches, although never very satisfactorily. Demonstrating the same determination he had displayed in facing other technical obstacles and in countering the derision of his contemporaries over his ambition for precise small movements and truly hermetic cases, Hans Wilsdorf embarked on the challenge of self-winding and turned it into the third pillar of the Oyster.

After several years of research, technical teams at the Manufacture des Montres Rolex in Bienne found a solution. As of 1931, Rolex registered a series of patents on a self-winding mechanism with a free rotor called “Perpetual”, which would later become the standard adopted by the entire watch industry. The watch could now wind itself while being worn; each movement of the wrist turning the rotor, which meshes with the mainspring.

Rolex FIRST OYSTER PERPETUAL watch circa 1931

The Rolex Perpetual system has a further advantage: the constant charging of the mainspring ensures greater regularity and enhances the precision of the watch movement. The Perpetual rotor effectively completes the Oyster concept: it improves precision, waterproofness and reliability while freeing the wearer of the watch from the constraint of manual winding.

And so the Rolex Oyster Perpetual was born, a watch so innovative, efficient and ahead of its time that its design fundamentally influenced the way all watches are made.

By establishing the standard for the precise, reliable, self-winding wristwatch, the Rolex Oyster Perpetual became the archetype of the modern watch, the watch that would change watches. All watches today are water-resistant to some extent and most modern mechanical watches are also self-winding, almost invariably inspired by the free rotor system perfected by Rolex. The brand has never since ceased to innovate in watchmaking and push back the limits of what is considered possible.

For 90 years, Rolex has always stayed one step ahead to fulfill the vision of its founder and apply its exceptional know-how to manufacturing exceptionally high-performance wristwatches.


Over the decades Rolex has developed an extensive collection of watches based on the Oyster Perpetual, with each new model responding to specific needs and uses.

The first Oysters, and later the Oyster Perpetuals, were such versatile watches that they could be worn in town as well as in extreme conditions by swimmers, racing drivers, aviators, mountaineers and explorers of every stripe, wherever essential equipment included a reliable and precise watch, capable of resisting the elements.

Rolex Oyster Perpetual Day-Date 40
Oyster Perpetual Day-Date 40

In 1945, to celebrate the 40th anniversary of its foundation, Rolex launched the Datejust, a high-prestige Oyster Perpetual in gold, with an innovative date display in an aperture at 3 o’clock on the dial.

From then on, two categories of Oyster came into being: particularly elegant classic watches with calendar functions, such as the Datejust, the Day-Date with its day and date display (1956), and more recently the Sky-Dweller with an annual calendar and a dual time zone (2012); and a second category consisting of specialized Oysters known as “Professional” watches, veritable tool-watches with additional features or functions for specific activities. The latter were often developed based on feedback from those using the original Oyster Perpetual in their given fled.

One of the first Professional Oyster watches, the Oyster Perpetual Explorer, was launched in 1953 after the first successful ascent of Everest. With its luminescent dial that was extremely legible in any circumstance and its steel bracelet, the Explorer stood out as a different kind of watch.

In 1953, Rolex also launched the Submariner, an Oyster Perpetual with reinforced waterproofness and equipped with a rotatable graduated bezel, specifically designed for deep-sea diving. In these versions of the Oyster, form followed function. Their names frequently reflected the category of user they were designed for.

These Professional watches also introduced many innovations, responding in the most practical, functional and reliable way possible to specific needs for measuring time. Explorer, Submariner, GMT-Master, YachtMaster and Cosmograph Daytona; each Professional model in the Oyster collection became a benchmark in its field, fully fledged archetypes of the explorers’, divers’, pilots’, skippers’ or racing drivers’ watch.

In designing its various models and in their future evolution, Rolex’s strategy is to always consider the watch as a whole. Innovation concerns cases, dials, bracelets and clasps just as much as the mechanical movement, in order to offer watches with increasingly better performance from every point of view: from precision and legibility, to accomplished ergonomics, comfort, reliability, resistance to the elements and external perturbations, and also aesthetics.

This approach encouraged the vertical integration of Rolex, and the brand’s in-house mastery extends to all of the essential components of its watches, from their external habillage to the movement inside, in accordance with the most demanding quality criteria at every stage. The insistence on enhancing performance also explains the typical gradual evolution of Rolex watches; new innovative features developed for one model are subsequently rolled out on others.

This is the case, for example, of the Cerachrom bezel, a high-technology component patented by Rolex, which is virtually scratchproof, corrosion resistant and impervious to ultra-violet rays. Launched in 2005 as a bezel insert on the GMT-Master II, it was then extended to the divers’ watches, the Yacht-Master models, and now appears in a monobloc version on the Cosmograph Daytona. In the movement, the paramagnetic blue Parachrom hairspring, developed and patented by Rolex, has also gradually been integrated into many models since 2000.


Rolex has registered more than 400 patents in the course of its history, and unceasingly innovates in order to continue to enhance the performance of its watches. The eight emblematic Oyster innovations described in the following pages have been developed and patented by Rolex over the last 90 years.

The Oyster Case – 1926

The Oyster was characterized first and foremost by its hermetic case, thanks to an ingenious patented system combining a screw-down bezel, case back and winding crown.

Rolex Oyster Case

Today, the Oyster case, entirely manufactured by Rolex, is waterproof to a minimum depth of 100 metres (330 feet) – 300 metres (1,000 feet) for the Submariner, and 3,900 metres (12,800 feet) for the Rolex Deepsea. Its middle case is crafted from a solid block of 904L steel, 18 ct gold or 950 platinum.

The fluted case back is hermetically screwed down with a special tool that allows only Rolex watchmakers to access the movement. (Today the bezel is no longer screwed down.) The winding crown screws down securely against the case offering watertight security akin to a submarine’s hatch. The robust waterproof Oyster case provides the high-precision movement with optimal protection from water, dust, pressure and shocks.

The Perpetual Rotor -1931

In 1931, Rolex invented and patented a self-winding mechanism with a free rotor, called the Perpetual rotor, based on a principle that would later inspire the whole watchmaking industry. The Oyster became an Oyster Perpetual. The Perpetual rotor consists of a half-moon-shaped oscillating weight rotating freely on its axle in both directions under the impetus of the wearer’s wrist movements. The rotor transmits energy to the mainspring, the motor of the watch.

Rolex Perpetual Rotor

Apart from increasing comfort for the wearer, who is freed from winding the watch every day, the Perpetual rotor helps to reinforce the Oyster’s waterproofness. It eliminates the need to regularly unscrew the crown, an operation which exposes the movement to dust and humidity.

By continuously winding the mainspring, the rotor maintains a stable high-level supply of energy to the movement, ensuring greater regularity and enhancing the precision of the watch. Self-winding via the Rolex Perpetual rotor provides excellent winding power in both rotation directions of the weight.

The Twinlock Winding Crown – 1953

The crown allows the wearer to adjust the essential functions of the watch, or wind it, by interacting directly with the movement. It is therefore crucial that the crown be dustproof and waterproof to complete the hermetic sealing of the case.

Rolex Twinlock Winding Crown

The Twinlock system, introduced and patented in 1953, guarantees that the screw-down winding crown is perfectly water-resistant thanks to two sealed zones, one inside the tube, the other inside the crown. The Twinlock winding crown was used on the Submariner at its launch in 1953, the first watch at the time waterproof to a depth of 100 metres (330 feet).

It maintained the waterproofness of the Oyster case even if the crown was not perfectly screwed down. It is now used on a number of models, to provide waterproofness down to a depth of 100 metres. The Twinlock crown is identified by two dots below the Rolex emblem on gold models, and on steel models by a bar.

The Parachrom Hairspring – 2000

In a mechanical watch, the oscillator is the guardian of time. Comprising a hairspring and a balance wheel, this organ determines the precision of the watch by the regularity of its oscillations. To ensure excellent precision, in 2000 Rolex introduced a patented hairspring in an exclusive alloy of niobium, zirconium and oxygen: the Parachrom hairspring.

Rolex Parachrom Hairspring

Entirely manufactured in-house by Rolex, this strategic component, half a centimetre in diameter, offers major advantages for precision timekeeping: it is insensitive to magnetic fields, offers great stability in the face of temperature variations and remains up to 10 times more accurate than a traditional hairspring in case of shocks.

In 2005, Rolex introduced a new patented process to modify the surface of the Parachrom hairspring and thereby further reinforce its long-term stability. This same treatment produces its characteristic blue colour.

The Paraflex Shock Absorber – 2005

In order to increase the resistance of its movements to shocks – particularly if dropped – Rolex developed and patented an exclusive and highly efficient shock absorber: Paraflex.

The balance wheel, the mechanical heart of the watch, is a moving component with great inertia that helps guarantee optimal chronometric performance of the watch. The pivots of the balance staff are one of the parts of the movement most susceptible to damage from shocks. They must be as fine as possible – around seven-hundredths of a millimetre in diameter, the thickness of a human hair – so as to minimize friction. This makes them extremely vulnerable.

Rolex Paraflex Shock Absorber

Rolex engineers developed a system that would increase the shock absorber’s resistance by 50 per cent while preserving the chronometric properties of the balance wheel. Special attention was paid to the spring, a key element that was completely redesigned. Its innovative geometry, developed using computer simulation, allows the shock absorber to withstand extremely demanding conditions. The new geometry of the shock absorber spring is an exclusive signature of Rolex movements.

The Cerachrom Bezel Insert – 2005

The bezel is one of the parts of a watch most exposed to shocks, scratches, corrosion and other environmental factors. Rolex developed and patented the Cerachrom bezel for particular Professional models in the Oyster collection. These bezels retain all of their beauty and functionality even in the most extreme conditions.

Rolex Cerachrom Bezel Insert

Manufactured by Rolex from a particularly hard, corrosion-resistant ceramic, this exclusive component is virtually impervious to scratches, and its colour is unaffected by ultraviolet rays. It also offers excellent polishability ensuring an exceptional, long-lasting lustre. For optimum legibility, the numerals and graduations are moulded in the ceramic and then coated with a very thin layer of either gold or platinum via a PVD (Physical Vapour Deposition) process.

The Syloxi Hairspring – 2014

The Syloxi hairspring is the optimal silicon hairspring according to Rolex. The fruit of several years of research and carrying five patents, this new and particularly innovative hairspring makes full use of the potential of silicon technology to bring an exceptional level of precision and reliability to the brand’s women’s watches. Adding to its range of high-performance hairsprings, it stands alongside the blue Parachrom hairspring that equips men’s models.

Rolex Syloxi hairspring

The Rolex Syloxi hairspring significantly improves the regularity of the oscillator and the precision of the watch. It is insensitive to magnetic fields, while offering great stability in the face of temperature variations. It also remains up to 10 times more accurate than a traditional hairspring in the face of the thousands of knocks a wristwatch receives on a daily basis.

The Rolex Syloxi hairspring further improves the performance offered by silicon technology by using new patented solutions, including the optimized geometry of the hairspring and an efficient design of its attachment systems.

The Chronergy Escapement – 2015

Positioned between the gear train and the oscillator, the escapement is the “key to time”, playing a crucial role in how the movement functions? It supplies energy to the oscillator – the component that determines the division of time – and, in turn, transmits those impulses to the hands via the gear train.

Rolex Chronergy Escapement

Rolex engineers devised and patented a new escapement that optimizes the efficiency of the Swiss lever escapement, the standard in Swiss watchmaking, but which had seen only limited technical evolution in the last 50 years.

While favoured by watchmakers for its great reliability, the Swiss lever escapement has always suffered from low efficiency, relaying to the oscillator barely more than a third of the energy it receives from the mainspring via the gear train.

The result of extensive research, the geometry of the new Rolex Chronergy escapement improves the efficiency of this key component by 15 per cent. It accounts for almost half of the increased autonomy of the new 3235 and 3255 movements. Made of nickel-phosphorus, the Chronergy escapement is, furthermore, resistant to magnetic interference.

[From the Highest Peaks to the Deepest Oceans]

To convince the world that the Oyster was waterproof – at a time when such a concept was barely conceivable – Hans Wilsdorf captured the imagination by demonstrating the capabilities of his new creation in real-life conditions. Rolex retailers in England were asked to display a goldfish bowl in their window with an Oyster watch submerged among the aquarium plants and fish.

In 1927, Hans Wilsdorf equipped Mercedes Gleitze, a young Englishwoman, with an Oyster when she swam the English Channel. After more than 10 hours in the water, the watch emerged in perfect working order. To celebrate this feat, Hans Wilsdorf published a full-page advertisement on the front page of the Daily Mail proclaiming the success of the waterproof Oyster watch – “the wonder watch that defies the elements” – and pronouncing it “the greatest triumph in watchmaking”.

Mercedes Gleitze later wrote to Hans Wilsdorf: “The reason I wear a Rolex Oyster wristwatch when swimming is because it is the only watch I know that is absolutely waterproof and also immune to damage from sand or salt air. Furthermore, I know that no other watch would stand up to the severe conditions experienced during long distance swims.”

This event marked the birth of the Testimonee concept and the beginning of a long and fruitful association between Rolex and exceptional personalities, whose accomplishments bear witness to the excellence of Rolex watches and give credence to the words of the 1927 advertisement: “[The Oyster] can be worn in the sea or bath without injury, nor would Arctic or tropical conditions affect the wonderful precision of its beautifully poised movement.”

Since then, many adventurers and pioneers have used Oyster watches at sea, in the air, in the depths of the ocean, on the highest peaks, and in the farthest and most hostile reaches of the planet. An explorer venturing into an extreme environment must be able to count on a timepiece that is accurate, reliable and robust.

In 1935, at the wheel of his specially built record-breaking car Bluebird, with an Oyster on his wrist, Sir Malcolm Campbell became the first man to break the mythical speed barrier of 300 mph (approximately 482 km/h). The “King of Speed”, at the height of his fame, had just pulverized the World Land Speed Record for the ninth time. He had worn a Rolex Oyster from 1930 onwards and attested to its exceptional resistance to shocks and vibrations in the advertisements of the time. After his last record-breaking feat, he telegraphed Rolex: “The Rolex watch is still keeping perfect time. I was wearing it yesterday when Bluebird exceeded 300 mph. Campbell.”

The first pilot to break the sound barrier (Mach 1), at the controls of an X-1 rocket-powered aircraft, in 1947, was also wearing a Rolex Oyster. On a signed photograph presented to Rolex founder Hans Wilsdorf, he wrote: “If you should build planes, they would be the fastest in the world!” . In 1967, William J. Knight, a test pilot with the United States Air Force, set a world aircraft speed record of Mach 6.72 (7,274 km/h) in his X-15 rocket-powered aircraft, an Oyster Perpetual GMT-Master on his wrist. The record still stands today.

Rolex began to forge privileged ties with the world of aviation during its golden age in the 1930s. Those were the years when spectacular progress in aircraft performance constantly expanded humanity’s capacity to conquer the skies, and led to the introduction of long-distance flights.

English aviator Charles Douglas Barnard, one of the pioneers of this era, set a number of flight records. Of the Oyster, he said: “The peculiar qualities of this Rolex watch render it eminently suitable for flying purposes and I propose to use it on all my long-distance flights in the future.” In 1933, Oyster watches accompanied the Houston Expedition as it made the first-ever flight over Mount Everest at an altitude exceeding 10,000 metres (33,000 feet) in extreme weather conditions.

In 1934, Owen Cathcart-Jones and Ken Waller made a return voyage from London to Melbourne (Australia) in record time with a twin-engine De Havilland Comet, using a Rolex Oyster as their on-board chronometer. In a letter to Rolex in 1935, Ken Waller wrote: “I relied faithfully upon my Oyster watch, and am glad to say that it has continued to behave with absolute precision, in spite of the great differences in climate and temperature, air pressure and many other causes which might have stopped such a tiny mechanism.”

As intercontinental travel developed in the 1950s, airliners began to fly swiftly across time zones. To meet the specific needs of pilots, Rolex developed the Oyster Perpetual GMT-Master, which displayed two different time zones simultaneously. It became the official watch of several airlines, among them the famous Pan American World Airways, known worldwide as Pan Am. The GMT-Master was used for navigation by the crew on the first non-stop intercontinental flight between New York and Moscow in 1959.

When Concorde, the Anglo-French supersonic passenger jet, made its final series of test flights at the end of the 1960s, the two British and French pilots were wearing GMT-Master watches.

Since the 1930s, the Oyster has accompanied numerous Himalayan expeditions. In 1953, Sir Edmund Hillary and Tenzing Norgay, members of a British expedition led by Sir John Hunt, were the first to reach Everest’s 8,848-metre summit. Sir John reported, “Rolex Oyster watches… performed splendidly, and we have indeed come to look upon Rolex Oysters as an important part of high-climbing equipment”.

The following year, in 1954, an Italian expedition equipped with Oyster Perpetual watches scaled the second highest mountain in the world, K2 (8,611 metres). Achille Compagnoni, one of the men who reached the top, wrote afterwards: “Your Rolex watch was with me during the whole expedition and worked perfectly, even above the 8,000-metre mark.”

In 1955, the world’s third highest peak, Kangchenjunga (8,586 metres), was summited by a British expedition. George C. Band, one of the climbers who accomplished this feat, reported: “I wore my Rolex Explorer throughout this expedition. You can guess how important it is to have a watch you don’t need to care about; it kept very good time, it wound itself and nothing seemed to harm it – water, snow or hard knocks.” Dr Charles Evans, the expedition leader, added: “My own Rolex has been of inestimable value to me.”

American climber Ed Viesturs is widely regarded as one of today’s greatest high-altitude mountaineers. Equipped with an Oyster Perpetual Explorer II, he has scaled the world’s most formidable summits 21 times, including seven ascents of Mount Everest. In 2005, he completed his Endeavor 8000 project: to climb the world’s 14 highest peaks – all exceeding 8,000 metres – without supplemental oxygen.

High-Altitude Expeditions Equipped With Rolex Oyster Watches:-

  • 1933 – British Mount Everest expedition
  • 1933 – Houston Expedition, first flight over Everest
  • 1934 – Expedition to Nanda Devi
  • 1935 – British Mount Everest reconnaissance expedition
  • 1936 – British Mount Everest expedition
  • 1937 – British reconnaissance expedition to Shaksgam
  • 1938 – British Mount Everest expedition
  • 1939 – Karakoram expedition
  • 1947 – Swiss Alpine Club expedition to Gangotri
  • 1949 – Swiss Himalayan expedition to Garhwal
  • 1952 – French Himalayan expedition to Garhwal
  • 1952 – Swiss Alpine expeditions to Mount Everest
  • 1952 – British Himalayan expedition
  • 1953 – British expedition reaches the top of Mount Everest
  • 1954 – Italian expedition reaches the top of K2
  • 1955 – British expedition reaches the top of Kangchenjunga
  • 1955 – French expedition reaches the top of Makalu

Caver and volcanologist Haroun Tazieff, an Oyster wearer since the 1950s, adopted the Explorer II, which he wore over his thermal suit in the heat of eruptions. In a letter addressed to Rolex headquarters in 1972, he wrote: “[My watch] has just passed, with flying colours, its first – and extremely demanding – volcanic test, in very aggressive gases on Mount Etna. It worked perfectly, which was not the case for the watches of my teammates.”

The chronometric precision of Oyster watches makes them ideal navigational instruments. In 1967, Sir Francis Chichester became the first yachtsman to circumnavigate the globe single-handed.

Returning to a hero’s welcome and knighted by the Queen for his achievement, he wrote in a letter in 1968: “During my voyage around the world in Gipsy Moth IV, my Rolex watch was knocked off my wrist several times without being damaged. I cannot imagine a hardier timepiece. When using [it] for sextant work and working the foredeck, it was frequently banged, also doused by waves coming aboard; but it never seemed to mind all this.”

The waterproofness of Oyster watches naturally predestines them for use in underwater exploration, in which Rolex has played a pioneering role since 1953, when it introduced the Submariner model, waterproof first to 100 metres (330 feet) and then to 300 metres (1,000 feet). In 1960, in the Pacifc Ocean south-west of Guam, the bathyscaphe Trieste, piloted by Swiss oceanographer Jacques Piccard and U.S. Navy Lieutenant Don Walsh, reached a record depth of 10,916 metres in the deepest point of the oceans in the Mariana Trench. Attached to the exterior, an experimental Oyster, the Deep Sea Special, withstood the colossal pressure of more than one tonne – 1 0 9 1 6 metres.

In the early 1970s, Rolex began collaborating with Comex (Compagnie Maritime d’Expertises), the world leader in marine engineering and deep-sea saturation diving. Rolex watches, particularly the Oyster Perpetual Sea-Dweller, waterproof to a depth of 1,220 metres (4,000 feet), were standard equipment for Comex.

They were the only watches the firm’s elite divers fully trusted on their saturation dives to great depths – when precise timing is of vital importance at every stage. In 1988, the Hydra VIII mission by Comex set the world open-sea diving record at a depth of 534 metres. In 1992, a Comex diver reached an experimental depth of 701 metres in a hyperbaric chamber. Both records still stand today.


In 2012, Rolex played an active part in film-maker (Titanic, Avatar) and explorer James Cameron’s DEEPSEA CHALLENGE expedition, in partnership with the National Geographic Society. On 26 March, the expedition descended 10,908 metres (35,787 feet) to reach Challenger Deep, the oceans’ deepest point, located in the Mariana Trench south-west of Guam in the Pacific Ocean.

A Rolex watch attached to the manipulator arm of the submersible accompanied James Cameron on the dive: an Oyster Perpetual Rolex Deepsea Challenge, an experimental divers’ watch specially developed and manufactured for the occasion. “The Rolex Deepsea Challenge was the reliable companion throughout the dive, it was visible on the sub’s manipulator arm and working precisely at more than 10,000 metres down at the bottom of Challenger Deep,” James Cameron said after his historic dive. “It’s a tremendous example of engineering know-how, and an ideal match for the DEEPSEA CHALLENGER submersible.”

The Oyster has proven its incredible reliability in the course of numerous expeditions on the pack ice of the poles. The many polar adventures include the British Trans-Arctic Expedition in 1969; the various expeditions, since 1976, of navigator and explorer Janusz Kurbiel to Iceland, to Greenland or in search of the magnetic north pole; Robert Swan’s expeditions to Antarctica; Erling Kagge’s conquest of the North Pole (1990), South Pole (1993) and Everest (1994); and Alain Hubert’s Arctic Arc expedition, a journey from Siberia to Greenland via the North Pole in 2007.

Wearing an Oyster, in 2006 Norwegian adventurer Rune Gjeldnes became the first and only person in the world to cross the three big ice sheets – Greenland, the Arctic Ocean and Antarctica – unsupported. In November 2005, Gjeldnes started on “The Longest March”, a three month, 4,800 km solo ski trek across the South Pole which he completed in February 2006. He now holds the records for the longest ski journey of any kind without resupply and the longest ski journey of all time. Of his Rolex watch, he said: “My Rolex is my ‘best friend’ on expeditions. It’s essential to have a precise and robust mechanical watch. I do trust my Rolex and it makes me feel safe knowing I can rely on it in the most difficult conditions.”

In 2010, a century after the conquest of the North Pole, eight pioneers of extreme frontiers took up a wild challenge between March and May – a polar expedition to learn about the underwater side of the Arctic. Their mission: discover and disclose what lies under the sea ice.

For 45 days, the team ski-trekked at the top of the globe in the Great Canadian North making dive after dive, bearing witness to an abundant ecosystem that is falling victim to global warming. In their luggage, still and video cameras and… five Oyster watches. “The only diving instruments which performed all the time were our Rolex watches – the Oyster Perpetual Rolex Deepsea model,” said Emmanuelle Périé, the team’s only woman member, after the expedition was over.

In addition to the votes of confidence from its Testimonies, over the years Rolex has received spontaneous messages of endorsement from many of its customers, delighted at the robustness and reliability of their Oyster. All mention the outstanding quality and longevity of Rolex watches, worn in conditions that are often just as extraordinary. Rolex published collections of many of these testimonials in 1957, 1969, 1981 and 1990.


Ninety years after its creation, the Oyster has again redefined horological performance. The criteria that made Rolex watches “Superlative Chronometers” in the late 1950s have now been reinforced to establish a new standard of excellence for mechanical watches.

Rolex has developed unparalleled testing methodologies and new high-technology equipment to certify each of its watches and award them the status of Superlative Chronometer. This exclusive designation attests that every watch has successfully undergone a series of special final controls conducted by Rolex in its own laboratories, and according to its own criteria which exceed watchmaking norms and standards. These tests complement the official COSC (Swiss Official Chronometer Testing Institute) certification of the movements.

The certification applies to the fully assembled watch, after casing the movement, guaranteeing superlative performance on the wrist in terms of precision, power reserve, waterproofness and self-winding. The precision of a Rolex Superlative Chronometer after casing is of the order of −2/+2 seconds per day, or more than twice that required of an official chronometer.

This precision is tested by Rolex using an exclusive methodology that simulates the conditions in which a watch is actually worn and is much more representative of real-life experience. The Superlative Chronometer certification also covers waterproofness – which protects the movement not only from water but also from all external elements that could compromise its precision – as well as the self-winding capacity and the power reserve, pledging that a watch will continue to function with precision over the long term.

These tests systematically complement the qualification testing upstream, during development and production, which ensures the reliability and robustness of the watches as well as their resistance to magnetic fields and shocks. The Superlative Chronometer status is symbolized by the green seal that comes with every Rolex watch and is coupled with an international five-year guarantee.

For each Rolex watch, the Superlative Chronometer certification comprises checks to guarantee the key areas of performance that may be disrupted during the course  of the manufacturing process – precision, power reserve, waterproofness and self-winding. All tests are conducted after the movement has been cased, to be as faithful as possible to the conditions under which the watch will be worn by its owner. Exclusive testing methodologies are employed, making use of entirely automated high-technology equipment developed by Rolex.

Each movement is submitted to COSC (the Swiss Official Chronometer Testing Institute) for its official certification, after 15 days and 15 nights of testing involving seven eliminating criteria in five static positions and at three temperatures. All Rolex movements obtain this official Swiss chronometer certificate. After casing the movement (an operation which can affect precision by several seconds per day), Rolex tests the precision of each watch over a 24-hour cycle, in seven static positions as well as in a rotating rack, according to an exclusive methodology that simulates real-life wear.

The tolerance criteria are much stricter than for the official certification with regard to the average rate deviation, the daily precision as perceived by the wearer. The deviation for a Rolex Superlative Chronometer must not exceed −2/+2 seconds per day, after casing, versus −4/+6 seconds per day required by COSC for the movement alone.

  • SELF- WINDING: The winding power of the Perpetual rotor self-winding module is checked by exclusive means to ensure that all the components interact optimally and are not subject to any obstruction or friction at casing.
  • WATERPROOFNESS : The waterproofness of each watch is tested a first time by subjecting it to excess internal air pressure and then by immersion in water in a hyperbaric tank. Watches guaranteed waterproof to a depth of 100 metres (330 feet) are tested at a water pressure equivalent to their rated depth plus 10 per cent, while divers’ watches – waterproof to 300,1,220 and 3,900 metres (1,000, 4,000 and 12,800 feet) – are tested with an additional safety margin of 25 per cent. The air tests and water tests are performed according to an exclusive methodology developed by Rolex to obtain extremely precise and reliable results.
  • POWER RESERVE:  All watches are fully wound at the beginning of the tests, and the power reserve of each watch is checked according to the specifications for the various movements by determining how long it runs before stopping.

The designation “Superlative Chronometer Officially Certified” inscribed on the dial of each Oyster is a true signature of Rolex watches. Formulated in the late 1950s, this inscription symbolizes the brand’s tireless pursuit of chronometric excellence, given the pioneering role it played in developing wristwatch precision from early in the 20th century. In 1910, in Switzerland, a Rolex became the first wristwatch to obtain official chronometer certification.

In 1914, a similar Rolex wristwatch was granted the first “Class A” precision certificate by the famous Kew Observatory in Great Britain, the highest authority in the world in terms of precision, and responsible for the certification of marine chronometers. Rolex’s invention of the Oyster in 1926, the first waterproof wristwatch in the world, was aimed primarily at protecting the high-precision movement from external elements.

The markings on the dial of Rolex watches have evolved over time to reflect the brand’s pursuit of precision. From “Chronometer”, it was changed to “Officially Certified Chronometer” in the late 1930s, before attaining its definitive form “Superlative Chronometer Officially Certified” some 20 years later. These various designations attest to Rolex’s continuous innovation to ensure the highest degree of precision for its watches over time and to perpetuate the excellence of the Oyster.

A chronometer is defined as a high-precision timekeeper officially certified for its capacity to measure time without deviating from the exact time by more than a few seconds per day. Currently, one of the seven eliminating criteria is the maximum tolerance for men’s mechanical watch movements: a loss of four seconds per day or a gain of six seconds per day. This precision must be attested to by an independent entity after 15 days and 15 nights of rigorous tests. In Switzerland, a movement that fulfils the criteria receives a chronometer certificate issued by the Swiss Official Chronometer Testing Institute (COSC).

But it was not always so. Before 1951, the regulations concerning the “chronometer” designation were quite different, with the official definition originally being “a precision watch […] having the capacity to obtain an official rating certificate”. A chronometer could thus be certified by its own manufacturer. To guarantee the quality of its chronometers, Rolex chose to have them officially certified. And, to underscore this difference, the brand changed the inscription on its dials in the late 1930s from “Chronometer” to “Officially Certified Chronometer”.

The Rolex Red Seal: Until recently, the Red Seal was attached to every Rolex which had been recognized as an “Officially Certified Chronometer.” Rolex are now raising their own standards even higher: henceforth no Rolex will be worthy of the title of “Chronometer” and bear a Red Seal unless it has obtained the very highest distinction for precision and quality from a Swiss Institute for Chronometer Tests : “Especially Good Results.”

In 1951, official certification became obligatory for all. A triumph for Rolex, which had produced almost 90 per cent of all the chronometers that had been officially certified since 1927. Rolex itself created a red seal to attach to each watch, with the inscription “Officially Certified Chronometer”.

But, wanting to continue to differentiate its chronometers from others, the brand set its sights on another goal: obtaining certificates avec mention (certificates of superior performance). According to the old rules, movements whose precision proved superior in the tests received a certificate with the citation “Especially good results”. From the early 1950s, Rolex founder Hans Wilsdorf became increasingly keen to have certificates avec mention, concluding by January 1959, “We have reached a point where we must obtain all our certificates avec mention!” and adding, “It is thus that the prestige of Rolex will increase”.

An important technical innovation paved the way for this achievement. In 1957, Rolex launched a new generation of movements, the 1500 calibres, equipped with a balance wheel with gold Microstella screws, offering excellent chronometric performance. (Today, Microstella nuts have replaced the screws.) The rate results achieved showed greater precision than the criteria for obtaining a mention. To mark these exceptional qualities, Rolex created the term “Superlative Chronometer”.

This designation would thereafter be added to the dial marking to constitute the well-known phrase “Superlative Chronometer Officially Certified”. It first appeared in the late 1950s on Datejust and Day-Date models. Since then, the meaning of the term has continued to evolve in order to reflect the technical development of Rolex watches and their performance, while always underscoring the notion that Rolex chronometers surpass the era’s standards.

Rolex’s goal has always been to produce watches of the highest quality, notably in terms of precision and reliability. Technological advances have opened up new opportunities and allowed the introduction of new criteria that exceed existing norms and standards, thereby fully justifying the qualification “Superlative” applied to Rolex Chronometers.

Already in 1927, the founder of Rolex, Hans Wilsdorf, had said about the precision of his watches: “We work to a gauge that cannot be measured by any instruments excepting our own.”

Rolex has always tested the performance of its watches according to its own standards, supplementing the testing with the official validation of its chronometers. After 1973, the creation of the Swiss Official Chronometer Testing Institute (COSC) consolidated the various official watch rating centres and led to the adoption of unified criteria which rendered mentions obsolete.

Rolex continued to legitimize the “Superlative” qualification of its chronometers with more extensive in-house testing of every single watch. Thus, in addition to testing the waterproof and dustproof qualities, which preserve precision over the long term, Rolex has, for decades, been testing the precision of its chronometers after casing the movements.

The new Rolex certification reflects the pursuit of its goal by adopting the strictest chronometric precision criteria in the industry, criteria which are more representative of real-life wear. This level of performance above and beyond the current standards can only be certified in-house. The brand can therefore offer its customers a superlative level of performance that pushes back the limits of mechanical watches and makes Rolex the benchmark of watchmaking excellence.

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