"This watch combines the toughness of G-Shock with the convenience of a light powered watch. And the Casio Wave Ceptor Atomic watches receive radio signals from the most accurate clock in the world - the cesium atomic clock at the National Bureau of Standards Black Ion Plated Case and Bracelet with Blue Ion Plated Bezel Light Powered - No batteries to change, ever! Shock Resistant 200 meter water resistant World time in 26 time zones, 30 cities Time recorder function - 30 records Daylight savings time on/off Auto Electro-luminscent backlight with afterglow 1/100 second stopwatch with measuring capacity up to : 23:59'59.99"" Stopwatch measuring modes: elapsed time, split time, 1st-2nd place times 4 alarms with snooze Hourly time signal Auto-calendar ( pre-programmed until the year 2039) 12/24- hour formats Accuracy: +/- 15 seconds per month"