The 2.4 G Hz Cateye HR-10 heart rate sensor will give you valuable physiological performance data that you can use to improve your training programme, or spot potential overtraining. Where power measures your effort through the pedals, a heart rate sensor lets you see into the impact this effort on your body. The Cateye HR-10 is compatible with Strada Digital, V3N & Q Series. The strap stays flat against your skin & doesn’t rub or chafe as you ride.