Sinn Spezialuhren 657 S

The Sinn 657 S, reference 657.020, is a watch in a 41 mm steel case with matte black chrome plating. A glossy black dial displays central seconds and the date under sapphire crystal. The case measures 12 mm thick and is water resistant to 200 metres. Self-winding calibre ETA 2824-2 is shock resistant. Minute ratcheting marks the bidirectional pilot's bezel, whose captive construction protects against loss. Magnetic Field Protection and a screw-down crown are further details of the construction.