Case diameter : 38 mm 50M Water Resistant,LED Light with Afterglow, Dual Time 1/100 second digital stopwatchMeasuring capacity: 23:59'59.99"Measuring modes: Elapsed time, split time, 1st-2nd place times 12/24 Hour Formats,Accuracy: +/-30 seconds per month, Battery CR2025 Band Type: Resin, Dial Code: Digital