Lithium battery. Water resistant. Battery life indicator. On/off confirmation sound. Automatic shut-off function. 2 Channel countdown timer. Split/lap time measurement. Memory recall during operation. Time and full automatic calendar. Store and recall of up to 10 split/lap times. Each channel can be preset for up to 100 hours. Measurable up to 100 hours in 1/100 of a second. Separate displays for split and lap time measurements. LED back-light illuminates display for easy viewing in low light situations. 1-Year .