Reactor Men's 'Gamma' Quartz and Stainless-Steel-Plated Watch, Color Grey (Model: 53608) 120-click unidirectional ratcheting timing bezel 10 year lithium battery with quartz day/date feature Japanese-quartz Movement Case Diameter: 45.5mm Water Resistant 200m (660ft):in General, Suitable for Professional Marine Activity and Serious Surface Water Sports, but not Diving