product specification Specifications 50M Water Resistant LED Backlight selectable illumination duration (1.5 seconds or 3 seconds) Dual time Hourly time signal 1/100 second stopwatch Measuring capacity: 23:59'59.99" Measuring modes: Elapsed time, split time, 1st-2nd place times daily alarm Hourly time signal Full Auto-calendar (pre-programmed until the year 2099) 12/24 hour formats Regular timekeeping: hour, minute, second, pm, month, date, day Accuracy: +/-20 seconds per month Approx. battery life: 10 years Battery: CR1620 Module: 3455 Size of case/total weight LW203 38.1 x 34.6 x 11.3mm / 20g