Ten years is a long time and that’s exactly why we used a battery that lasts just as long. Equipped with E-Data memory and 4 multi-function alarms, you’ll never miss a step. 10 Year Battery Life Shock Resistant 200M Water Resistant Auto EL Backlight with Afterglow E-Data Memory Memory capacity: Up to 40 sets of data (when there are 7 characters per record) Actual number of records depends on number of characters per record Password protected World Time 29 time zones (27 cities), city code display, daylight saving on/off 4 Multi-function Alarms & 1 Snooze Alarm Countdown Timer Measuring unit: 1 second Countdown range: 1 minute to 24 hours Auto-repeat Function 1/100 second stopwatch Measuring capacity: 23:59’59.99″ Measuring modes: Elapsed time, split time, 1st-2nd place times Auto Calendar (pre-programmed until the year 2039) 12/24 Hour Formats Accuracy: +/-15 seconds per month Battery CR2025 Approx. battery life: 10 years Module 2548 Size of case/total weight G2900 52.4 x 45.9 x 16.5mm / 58g