The first deck watches, also known as B-Uhr watches, are considered to be the marine time pieces developed in the 18th century by English watchmaker John Harrison. They represented an important development in nautical navigation. Over time, deck watches became particularly established in the military, where they were used for locating and navigation, for coordinating procedures and for keeping schedules.
With the 856 B-Uhr, German watch brand Sinn continues this tradition, combining the characteristic, historic look of a B-Uhr with a comfortable 40 mm diameter. As is customary with traditional B-Uhr watches, the hour hand of the 856 B-Uhr has been reduced. It points to a separate, inner hour circle, while the dominant minute hand indicates the minutes around the outside.
Just like the numerals, indices and triangular main marker, the minute hand is highlighted by an ivory-coloured coating. The ordering of hour hand and minute hand on the black dial follows historical specifications: during operations, minutes were the more important unit of time, and it was important to be able to read them quickly and accurately.
The high-tech features of this watch fulfil all the criteria of a deck watch: functionality, durability, readability, precision and reliability. The surface of the bead-blasted stainless-steel case has been hardened using TEGIMENT Technology, making it especially scratch resistant, while Ar-Dehumidifying Technology guarantees greater functional reliability and freedom from fogging. In order to minimise magnetic interface, the 856 B-Uhr is equipped with Magnetic Field Protection up to 80,000 A/m or 100 mT. A total of 856 of these unusual watches are being produced, each with an engraved limited-edition marking on the case back.
25 bearing jewels
28.800 semi-oscillations per hour
Seconds stop function
Shock resistant as per DIN 8308
Anti-magnetic as per DIN 8309
Case made of stainless steel, bead-blasted
Sapphire crystal glass in front, anti-reflective on both sides
Case back screw-fastened, nickel-free
Meet the technical requirements for water-proofness, as set out in standard DIN 8310
Pressure-resistant to 20 bar
Low pressure resistant
Hours, minutes, seconds
TEGIMENT Technology, therefore especially scratch-resistant
Ar-Dehumidifying Technology enhances functional reliability and freedom from fogging
Magnetic Field Protection up to 80,000 A/m
Dimensions and Weight
Case diameter: 40 mm
Band lug width: 20 mm
Case thickness: 11 mm
Weight without strap: 70 gramme
Dial and Hands
Matte black dial
Numbers and indices coated with luminescent colour
Hour, minute and second hand coated with luminescent colour