Polar Loop Cable Use the USB cable to charge your Polar loop Sync your activity and training data from your device Use with the Polar flow web service to analyze data Wristband Size : 9  . NOTE - Measurements taken from the LAST HOLE to the END OF RUBBER next to buckle (not from end to end). *Loop is from end to end prior to cutting. Wristband Size : 9  . NOTE - Measurements taken from the LAST HOLE to the END OF RUBBER next to buckle (not from end to end). *Loop is from end to end prior to cutting.