When it comes to accuracy and connectivity, the Polar H10 heart rate sensor is the only way to go. Track your heart rate with maximum accuracy and link your heart rate via Bluetooth® and ANT+ with various training devices. The heart rate belt has a sturdy buckle that ensures that the sensor remains in good contact with your skin. Silicone elements have been used on the strap, which keep the sensor in place against your chest, so that it can optimally measure your heart rate. The soft textile chest strap ensures maximum comfort when wearing the sensor, however long you wear it.