POLAR T31 Coded Chest Transmitter and Elastic Strap

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Transmits heart rate data to Polar heart rate monitors using 5kHz transmission and compatible gym equipment. Compatible heart rate monitors include, but are not limited to: FT1, FT2, FT4, FT7, FT40, FT60, FT80, RS100, RS300X, RS400, RCX5

Compatible products:Elastic straps.Individually coded to pick up your heart rate monitor and not others nearby. This eliminates cross-talk with other electronic devices in the same area.

Slim, lightweight, and waterproof design

Fits 25 to 54 inch chest size

Average battery lifetime is 2500 hours of use. Non user replaceable battery