Mineral Glass Shock Resistant Mud Resistant 200-meter water resistance Case / bezel material: Resin Resin Band Electro-luminescent backlight Auto light switch, dual illuminator, selectable illumination duration, afterglow Flash alert Flashes with buzzer that sounds for alarms, hourly time signal, countdown timer time up alarm, countdown timer progress beeper, and stopwatch auto start Low temperature resistant (-20°C) World time 29 time zones (48 cities), city code display, daylight saving on/off 1/100-second stopwatch (ST1) Measuring capacity: 999:59'59.99'' Measuring modes: Elapsed time, split time, 1st-2nd place times Other: Auto start 1/100-second stopwatch (ST2) Measuring capacity: 999:59'59.99'' Measuring modes: Elapsed time, split time, 1st-2nd place times Countdown timer Measuring unit: 1 second Countdown range: 24 hours Countdown start time setting range: 1 minute to 24 hours (1-minute increments and 1-hour increments) Others: Auto-repeat, progress beeper Multi-function alarms 5 independent multi-function alarms (4 one-time alarms and 1 snooze alarm) Hourly time signal Full auto-calendar (to year 2099) 12/24-hour format Button operation tone on/off Regular timekeeping: Hour, minute, second, pm, month, date, day Accuracy: ±15 seconds per month Approx. battery life: 3 years on CR2025 Size of case/total weight: 52 X 46.3 X 16.3 mm/56 g EL:White EL:Blue Green