The Polar T31 Coded Chest Transmitter is a heart rate monitor designed for gym and training activities. It is made of black plastic and has a medium size elastic strap for comfortable wear on the torso. The device is powered by batteries and has a battery life of 2500 hours. It features a chest strap for accurate heart rate measurement and comes in English language. The device has a model number POLAR T31 and is manufactured by Polar.
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