Introduced in 1971, Rolex Oyster Perpetual Explorer II is an extreme professional watch, and highly valued by mountaineers and speleologists, for its rugged durability and reliability in countless expeditions to every corner of the globe.
The first every Rolex Explorer II watch (reference 1655) features a 39mm diameter case in stainless steel and houses the self-winding caliber 1575 GMT. In 1985, this model was replaced with reference 16550, which features a 40mm stainless steel case and the self-winding caliber 3085.
Introduced in 1989, the reference 16570 houses the Caliber 3185 movement (the models produced from 1989 to 2006) or Caliber 3186 (the models produced since 2007).
Equipped with an additional, red 24-hour hand and a fixed 24-hour graduated bezel, the Explorer II allows simultaneous reading of the time in two time zones and makes it possible to distinguish night hours from day hours, a necessity for speleologists or polar explorers.
It is equipped with a 12-hour hand that can be set independently from the minute hand, thus allowing the wearer to set the watch for a new time zone while the minute hand continues to function, maintaining the exact time.
The Oyster Perpetual Explorer II has over time confirmed its qualities of robustness and reliability during numerous expeditions. The original Explorer model was the watch that, in 1953, accompanied Sir John Hunt, Sir Edmund Hillary and Tenzing Norgay on their victorious ascent of Everest.
Self-winding, equipped with a Perpetual rotor and certified by the Swiss Official Chronometer Testing Institute (COSC), the Oyster Perpetual Explorer II is guaranteed waterproof to a depth of 100 metres (330 feet). It features a sapphire crystal with a Cyclops lens and a Twinlock winding crown protected by shoulders.
Rolex Caliber 3185 Vs 3186
Rolex Caliber 3185 is a self-winding movement featuring a second time zone function in addition to the hour, minute, seconds and date display. Belongs to Rolex 3100 caliber family and introduced in 1989 as the replacement of Caliber 3085, this movement features an independently adjustable GMT hand. This 31 jewel movement has a power reserve of approximately 50 hours.
Measuring 28.50mm diameter and 6.45mm thickness, Caliber 3185 has a beating frequency of 28,800 v.p.h. All the four hands are centrally placed and the date display is positioned at 3H. It also features functions such as Hacking Seconds, Hand-Winding Capability, Instant Date Change and Quick Date Correction. This movement is used with Rolex Explorer II Ref. 16570 watches produced from 1989 to 2006.
In 2005, Rolex introduced Caliber 3186 as the replacement of 3185. In this new movement, Rolex solved the issue of wobbling action of 24H hand existed in Cal. 3185. In the Caliber 3186, Rolex used a blue Parachrom hairspring where as the Cal.3185 features a Nivarox spring. Other technical features are same for both the calibers. The Caliber 3186 can be found in Rolex Explorer II Ref. 16570 models produced from 2007.
Technical details
Model: Rolex Oyster Perpetual Explorer II (reference 16570)
Movement
Calibre 3186, 31 jewels
Self-winding: Perpetual rotor
Power reserve: 48 hours
Date: Instantaneous change
Oscillator Frequency : 4 Hz (28,800 beats/hour), hairspring with a Breguet overcoil
Chronometer: COSC certification
Case
Diameter: 40 mm
Material: 904L steel
Case: Fixed 24-hour graduated bezel, shoulders to protect the crown
Waterproofness: 100 m (330 ft)
Winding crown: Twinlock
Crystal: Sapphire with Cyclops lens
Bracelet
Oyster with Oysterlock clasp
