At a glance This model comes in a medium sized case and has 50m Water Resistance. The feature packed model also has an EL backlight with Auto light switch that illuminates the display when the watch is angled toward the face, plus Dual Time, Auto Start Stopwatch, Auto Repeat Countdown Timer, and more. Overview: Water Resistant 50 Metres 1/100 Sec Stopwatch Daily Alarm Electro-Luminescent Backlight Afterglow Countdown Timer 12/24 Hour Format Auto-Calendar Dual Time Spherical Lens Specifications: Accuracy +/-30 sec's per month Approximate battery life 2 years on CR1616 Measuring capacity 23:59'59.99" Measuring modes Elapsed time, split times, 1st-2nd place times Measuring modes Others: Target time alarm, auto-start function Regular timekeeping Hour, minutes, seconds, am/pm, month, date, day Countdown Timer Input range: 1 minute to 24 hours Unit:1/10 Second Other: Auto-repeat function, progress beeper function Hourly time signals