"Polished Stainless Steel Case and Bracelet Citizen Eco Drive Solar Powered Technology so you never have to change a battery One Year Power Reserve when fully charged without additional exposure to light (72 hours with average lighting to fully charge) Mineral Glass Crystal Water Resistant to 30 Meters (100 Feet) Bracelet features a Jeweler's Style Clasp 21mm Case Width (Approximately 3/4"")"