Casio General x Digital ft. Lightweight Army Unisex Casual Hexagon Water Resistant Watch F-91W-1D F91W F91 F-91 F-91W Experience precision and style with this digital watch, featuring a long-lasting 7-year battery life, LED light, and water-resistant design. Enjoy advanced functionality, including a 1/100-second stopwatch, daily alarm, and auto-calendar, all in a lightweight and comfortable resin case and band. Module / Movement 593 (quartz) Battery Life / Accuracy Approximately 7 years (+/-30 seconds per month) Crystal Resin glass Light LED light Case / Band Material Resin case with resin band Water Resistance Water resistant Case Size Thickness: 8.5 mm Diameter: 35.2 mm Length: 38.2 mm Lug width: Integrated Other Specifications Casio General x Digital ft. Lightweight 1/100-second stopwatch (up to 60 minutes, elapsed time, split time) Daily alarm Hourly time signal Auto-calendar (set at 28 days for February) 12/24-hour format Regular timekeeping (digital display)