Sinn Spezialuhren 917

The Sinn 917, reference 917.011, is a chronograph with a polished 44 mm steel case. A rotating countdown bezel surrounds the dial. The case is 15.5 mm thick and water resistant to 100 metres, with a see-through back and screw-down crown. Beneath sapphire crystal, the displays include the date, weekday and small seconds. Calibre Valjoux 7750 uses a self-winding mechanism. Ar-Dehumidifying Technology helps prevent fogging and enhances functional reliability.