World Time. Electro-Luminescent Backlight with Afterglow. 50 Meter Water Resistant. Atomic Watch Receives time calibration radio signals which keep the displayed time accurate. Time calibration signal reception. Auto receive function (one time per day at 1:00am). Manual receive function. World time 29 time zones, 30 cities. Daylight savings time on/off. Date alert. Display flashes when set date is reached. 1/100 second stopwatch. Measuring capacity: 99:59'59.99. Measuring modes: elapsed time, split/lap time, 1st-2nd place. 5 Alarms. Auto-calendar (pre-programmed to year 2096). Accuracy: 20 seconds per month (with no signal calibration). Approx. battery life: 2 years on CR1620. The Casio Atomic Powered watches receive a time calibration signal transmitted from Fort Collins, Colorado. Signal reception is possible within a radius of about 2,000 miles from the Fort Collins transmitter. See manual for an explanation of ideal conditions for setting as well as factors or locations that can create and make reception difficult.