Citizen Men's BM8400-50A Eco-Drive Corso Stainless Steel Watch Light powered Eco-Drive Caliber E101 Japanese-quartz movement; charges in natural sunlight or indoor light Max power reserve: 180 days; low charge warning: 4 days; Quick start ability; charge time from stop state to max charge: Incandescent Light - 120 hrs, Outdoors, Cloudy (10,000 Lux) - 35 hrs, Outdoors, Sunny (100,000 Lux) - 11 hrs Durable, hardened mineral crystal; case diameter: 39 mm Stainless-steel case; silver dial; day-and-date functions Water resistant to 330 feet (100 M): suitable for snorkeling, as well as swimming, but not diving