Timex Ironman Race Trainer Mid Monitors Imported Preset your Desired Heart Rate Target Zone to One of Six Ranges, Review Workout Average and Peak Heart Rate 10-Workout Memory automatically saves latest workout, Lock past workouts, Review Time-In-Zone and Calories Burned 100-hour chronograph with lap and split, either in large digits, 50-lap memory per workout with average heart rate per lap, 5-Segment Interval Timer with Training Zones, 2-mode countdown timer, 3 Alarms with 5-minute backup, INDIGLO night-light with NIGHT-MODE feature Owner-Replaceable Battery; Data Xchanger USB compatible; water resistant to 100m