Features
: For Swimming, Water Resistant
At the heart of your training is the Polar T31 Coded Transmitter. 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. Compatible heart rate monitors include, but are not limited to: FT1, FT2, FT4, FT7, FT40, FT60, FT80, RS100, RS300X, RS400, RCX5.