Garmin Garmin Cadence Sensor 2

No magnets & easy to move between bikes. Monitor your cadence as you ride with these easy-to-install wireless sensors. With no magnets or other exposed parts to line up, these sensors are easy to install, maintain and move between bikes. Send live cadence data to compatible training apps or displays by using ANT+® connectivity and Bluetooth® Low Energy technology. With both of these sensors on your bike, you can work to improve your personal best or see where you stand against the pros. The Cadence Sensor 2 fastens to any size crank arm and measures pedal strokes per minute so you can get the most out of your training.