Always be on perfect time with this unique watch. Atomic timekeeping: Receives time calibration radio signals 3 times a day which keep the displayed time accurate. You can also manual receive the signals. The signal is WWVB with a frequency of 60kHz. Tough solar power. Shock resistant. 200M water resistant. Auto EL backlight with afterglow. World time with 29 time zones, 30 cites, city code display, daylight saving on/off. 4 daily alarms and 1 snooze alarm. Countdown time with a range of 1 minute to 60 minutes. 1/100 second stopwatch with measuring modes of elapsed time, split time, and 1st-2nd place times. Hourly time signal. Pre-programmed auto calendar. 12/24 hour formats. Battery CTL 1616. Battery power indicator. Power saving function. Approximate battery life of 11 months on full charge (without further exposure to light). Module 2913. Size of case/total weight: 51.3 x 46.0 x 15.0mm/58g.