Just in case anyone is thinking of buying this, it's a great piece of kit and feeds into Polar's personal trainer website where you can analyse your heart rate during matches and training. In conjunction with the footpad available. you can also track your distance and speed.
Just a quick note of caution though, last time I checked (about 4 minutes ago) Polar announced these were no longer regarded as "current" and as such they would not provide any Windows 10 support for the USB dongle. The windows 8 drivers will install but Windows 10 will not set up the IrDA dongle.