100- meter water resistance, LED backlight, Dual time, Daylight saving on/off, stopwatch, Countdown timer, 3 multi- function alarms Hourly time signal, Full auto- calendar 12/24- hour format, Button operation tone on/off, Approx. battery life: 10 years on CR2025 Quartz Movement Case Diameter: 42.6mm Water resistant to 30m (100ft): in general, withstands splashes or brief immersion in water, but not suitable for swimming or bathing