LED lightAuto light switch, selectable illumination duration (1.5 seconds or 3 seconds), afterglowWorld time29 time zones (48 cities + coordinated universal time), daylight saving on/off, Home city/World time city swapping1/1000-second stopwatchMeasuring capacity: 99:59'59.999''Measuring modes: Elapsed time, lap time, split timeOthers: Speed (0 to 1998 units/hour), Distance input (0.0 to 99.9)Mach indicator (speed exceeding 1225 units/hour)Countdown timerMeasuring unit: 1 secondCountdown range: 24 hoursCountdown start time setting range: 1 minute to 24 hours (1-minute increments and 1-hour increments)Other: Auto-repeat5 daily alarms (with 1 snooze alarm)Hourly time signalFull auto-calendar (to year 2099)12/24-hour formatRegular timekeepingAnalog: 2 hands (hour, minute (hand moves every 20 seconds)), 1 dial (speed)Digital: Hour, minute, second, pm, month, date, dayAccuracy: ±15 seconds per monthApprox. battery life: 2 years on CR1220