The Polar G3 WIND GPS Sensor sends a speed & distance signal to a Polar WIND heart rate monitor. The monitor will displays and record speed/pace and distance measurement for outdoor sports like running and cycling, horse riding, cross country ski etc.G3 speed range is 0 - 18.3 mph (0 - 30 km per hour)Durable and water-resistant G3 sensor is compatible with RS800cx, CS600Sensitive, built-in SiRFstarIIITM GPS technology, the sensor provides highly reliable GPS reception even in wooded areas.Kit includes sensor, strap, storage pouch, user manual and alkaline battery.