"Accuracy at Normal Temperature: +/-15 Seconds/Month Timekeeping Mode: Hours, Minutes, Seconds, am/pm, Month, Date, Day, Auto-Calendar (Does Not Calculate Leap Years) Alarm Mode: Daily Alarm, Hourly Time Signal Countdown Alarm Mode: Measuring Unit 1/10 Second, Input Range from 1 Second to 60 Minutes Stopwatch Mode: Measuring Unit: 1/100 Second Measuring Capacity: 23 Hours, 59 Minutes, 59.99 Seconds Measuring Modes: Elapsed Time, Split Time, and Two Finishes Auto-Start Function Target Time Function Water Resistant to 200 Meters Electro-Luminescent Backlight with Red ""G"" Backlight Flashes when Alarm or Signal Sounds Battery: CR2016 Battery Life: Approximately 2 Years with Normal Use 50mm Case Width (Approximately 2"") 16mm Case Thickness (Approximately 5/8"")"