Model 857 (and similar EZM 7) is an instrument watch by Sinn produced since 2007.
Sinn introduced the model 857 as an update to the Sinn 657. It features a larger 43 mm case (up from 41 mm), TEGIMENT case, and Ar-Dehumidifying technology. As was the case with the 657/656, a smaller version with a fixed bezel is also produced, the Sinn 856. But the 857 has a bi-directional movable pilot's bezel. The watch is magnetic field protected.
Sinn also produced UTC versions, which allow a second timezone to be read using a movable central hour hand.
In 2010, Sinn created the EZM 7, a Mission Timer for fire brigades. Essentially identical to the existing Sinn 857, the EZM 7 rotates the case 180 degrees so the crown is on the left side of the dial. The inner portion of the dial features scales measuring important aspects of firefighting. An EZM 7 S was added as well.
- See Also: Sinn 856
- 857 (2007-present)
- 857 S (2009-present)
- 857 S UTC (2011-present)
- 857 UTC (2011-present)
- 857 UTC TESTAF (2013-2017)
- 857 UTC TESTAF LH Cargo (2014-present)
- 857 UTC VFR (2017-present)
- Mechanical movement (ETA 2893-2), 28,800 A/h
- Nivarox 1 hairspring, Glucydur balance wheel, Beryllium plateau
- Mainspring Nivaflex 1, Incabloc shock absorber
- Tegimented stainless steel case, bead-blasted
- Ø 43.0 mm, height 12.2 mm
- Pilot's bezel : stainless steel, hardened with Tegiment technology, captive, bidirectional rotating and latching in minute intervals; black anodized aluminum ring with luminous triangle
- Nickel-free caseback
- Sapphire crystal with anti-glare treatment on both sides
- Screw-in crown with double o-ring gasket
- Magnetic field protection up to 80.000 A/m
- Waterproof to 200 m
- Safe below atmospheric pressure
- Hours, minutes, seconds, date
- Dual time zone on 24 hours basis
- Black, indexes and numerals with special white, long-lasting luminous paint
- Internal 24 hours scalein white
- UTC letters in daylight color, UTC hands with daylight color
- Cowhide leather strap
- Variants: Solid stainless steel bracelet, tegimented and black hard-coated
- Production: 2007-Present
- Predecessor: Sinn 657