път Разочароващ барел sensor polar може би оптимизъм развитие на
Polar Stride Sensor Bluetooth Smart | NavWorld
Polar H10 | Heart rate monitor chest strap | Polar United Arab Emirates
Amazon.com : Polar Verity Sense - Optical Heart Rate Monitor Armband for Sport - ANT+ and Dual Bluetooth HRM - Waterproof HR Sensor with only One Button - Compatible with Peloton, Zwift