Prospex Solar Diver's WatchPowered by light energy - no battery change required10-month power reserve once fully chargedBlue and red uni-directional rotating elapsed timing bezelBlack dialDate calendarLumiBrite hands and markersSapphire crystalScrewdown crown and casebackCase diameter: 42.8mmStainless steel case and braceletTri-fold push button release clasp with secure lock and extenderWater-resistant to 200 meters (660 feet), Diver's Watch. Follows ISO standards and is suitable for scuba divingCaliber V157