Tommy Hilfiger Women's 1780818 Black Automatic Leather Strap Watch Quality Automatic movement; Functions without a battery; Powers automatically with the movement of your arm Watch does not require battery to operate, watch powered by the movement of your arm Much like the pendulum on a grandfather clock, a counterweight inside an automatic watch winds its gears with the motion of a wearers daily activity Stainless steel case; Mother of Pearl center zone; Black leather strap Water resistant to 99 feet (30 M): withstands rain and splashes of water, but not showering or submersion