Casio G-Shock x Master Of G ft. GravityMaster Men Casual Sports Round 200m Water Resistant Watch GR-B100-1A3 GRB100 GR-B100 Experience precision timekeeping and rugged durability with the GR-B100 GravityMaster, designed for pilots and adventurers who demand the best. Featuring advanced navigation, atomic timekeeping, and a robust design, this watch is built to withstand the toughest environments. Battery Life / Accuracy Tough solar (6 months without exposure to light) (+/-15 seconds per month) Crystal Mineral crystal Light Double LED light (full auto LED light, super illuminator, selectable illumination duration, afterglow) Case & Band Material Resin / stainless steel case with resin band Water Resistance 200m / 20 bar Case Size Thickness: 17.3 mm Diameter: 53.8 mm Length: 62.5 mm Other Specifications Casio G-Shock x Master Of G ft. GravityMaster Shock resistant Mobile link (wireless linking via Bluetooth) World time (39 time zones) 1/1000-second stopwatch Countdown timer 5 multi-function alarms Hourly time signal Full auto-calendar (to year 2099) Button operation tone on/off Power saving (display goes black and hands stop to save power when left in the dark) Battery level indicator 12/24-hour format Hand shift feature Regular timekeeping (analog-digital display)