50M Water Resistant. Micro Light. Dual Time. Muli-function Alarm. Countdown Timer. Measuring unit: 1 second. Countdown range: 1 second to 24 hours. Auto-repeat function. 1/100 second digital stopwatch. Measuring capacity: 23:59'59.99". Measuring modes: Net time, split time, 1st-2nd place times. Hourly Time Signal. Auto Calendar (pre-programmed until the year 2029). Accuracy: +/-15 seconds per month. Battery CR2016. Approx. battery life: 5 years. Module 549.