The Polar RS800CX Heart Rate Monitor works with Polars WearLink+ transmitter and all WIND sensors (sold separately) to compile accurate training statistics while you run or bike. The RS800CX not only records your heart rate, it can also log distance, time, calorie expenditure, elevation, and speed. Upload these training stats to your computer using Polars ProTrainer 5 software (sold separately) so you can analyze your progress and make adjustments to your training regimen. Product Features Material: [Housing] plastic; [Strap] rubber Altimeter: Yes Barometer: No Heart Rate Monitor: Yes Chronograph: Yes Thermometer: No Digital Compass: No Adjustable Declination: No Low Battery Indicator: Yes PC Compatible: Yes Waterproof: Water resistant to 50m Backlight: Yes Alarms: 1 Time, 1 target heart rate Battery Type: User-replaceable Battery Life: Size: Weight: Recommended Use: Running, biking, adventure race training Manufacturer Warranty: