this solar powered watch recharges itself in any kind of lightthis solar watch does not require any battery replacement - the watch has a calendar function: date solar powered stop watch 24-hour display luminous numbers luminous hands high quality 21 cm length and 20 mm width silver titanium strap with a fold over with push button clasp case diameter: 40 mmcase thickness: 10 mm case colour: silver and dial colour: blue water resistant: 10 bars-weight: 94 g Department name: mens Band size: Mens Standard Band width: 20.0 Case diameter: 40.0 millimeters Clasp type: Folding clasp with push button Target gender: male Water resistance depth: 100.0 meters Dial window material type: Mineral Item shape: Round