Seiko Men's Quartz Stainless Steel Casual Watch, Color:Silver-Toned (Model: SKA347) Kinetic movement; functions without a battery; powers Kinetically with the movement of your arm Strong Hardlex crystal protects dial from scratches Case diameter: 40 mm Stainless-steel case; black dial; date function Water resistant to 330 feet (100 M): suitable for snorkeling, as well as swimming, but not diving