Polar T31 Coded Transmitter
At the heart of your training is the Polar T31 Coded Transmitter Set. Its purpose is simple; to transmit your heart rate to your wrist unit. Slim and light, the ECG (electrocardiogram) accurate transmitter is fully water resistant and designed for all weather conditions. Prevents cross-talk from other electrical devices for accurate measurement of your training. It is built to last with up to 2500 hours of training usage. No user replaceable battery. Fully water resistant.