The CatEye CDC-30 Magnetless Cadence Sensor is the perfect choice for cyclists of all experience levels. With no magnets required, it installs quickly and easily on all bicycle types and offers dual band Bluetooth and ANT wireless connection to both smartphones and your CATEYE bike computer. Featuring an integrated accelerometer and IPX7 waterproof rating, it also includes a rubber strap for easy attachment to your bike's crank arm.