Workout at your convenience with the Sunny Health & Fitness SunnyFit Bike Cadence. Its 2 LED lights indicate the sensor's device connection and mode, flashing to show its status: power on, wake up, broadcast, and connect. The SunnyFit app tracks and views your time, speed, RPM, distance, and calories in real time, and it is simply placed onto the protective, rubberized mat then wrap and secure around the bike's crank with the taut elastic bands provided for a snug and secure attachment. Secure the sensor onto the flywheel axle instead for outdoor cycling. Sunny Health & Fitness SunnyFit Bike Cadence - Exer Bike/Ski Machine at Academy Sports