Seiko Men's Quartz Stainless Steel Sport Watch, Color:Black (Model: SNP017) Kinetic movement; functions without a battery; powers Kinetically with the movement of your arm Strong scratch resistant sapphire crystal Case diameter: 41.5 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