The Garmin Speed and Cadence Sensor Bundle will allow you to monitor your speed and cadence as you ride all in one easy-to-install wireless sensor bundle. With no magnets or other exposed parts to line up, these sensors are easy to install, maintain and move between bikes. The Speed Sensor 2 attaches to the hub of either wheel and self calibrates with your Edge cycling computer or compatible Garmin device to give you accurate speed and distance at all times. Can operate without a head unit and is great to pair direct with tablet/phone for training software via Bluetooth. Garmin Speed and Cadence Sensor Bundle Features 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 Send live speed, distance and 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 By each sensor singly, or in the everyday value bundle