Tommy Hilfiger Men's 1710140 Automatic Black Leather Watch Quality Japanese-Quartz movement The motion of a wearers daily activity - walking, having a drink of water - keeps the counterweight moving so the watch runs. An automatic watch can store up to 40 hours of power. If it stops after a day or two of non-use, wind the crown and give it a gentle shake to start the movement again. Once reserved for the priciest timepieces in the world, our automatic movements let our customers purchase fully self-winding automatics that are entirely battery-free! Water resistant to 99 feet (30 M): withstands rain and splashes of water, but not showering or submersion