This is a multi-functional cycling meter, which can record and display cycling speed in real time, can record calorie consumption, can measure temperature, display total mileage, and so on. And the installation is simple, do not need wiring. Bring you more riding fun with ease. Features: Multi-function: display time, temperature, speed, tread frequency, measure calories, average speed, maximum speed, total mileage and cycling time. With 7 days memory function and stopwatch function. Full-screen backlight, barrier-free data observation at night (press the left and right buttons at the same time to turn on/off backlight). Support two different tire sizes of bikes to record data together. USB charging, 150h standby time, 15h working time. The data test is stable and accurate. Daily waterproof, not afraid to ride in rainy days. Specifications: Main color: black Material: ABS+metal Mileometer battery: 3.7V, 1200mAh Sensor battery: CR2032, 3V, 240mAh Mileometer size: 64 * 40 * 13.5mm / 2.5 * 1.6 * 0.5in Mileometer weight: 30g / 1.1ounce Package size: 198 * 121 * 30mm / 7.8 * 4.7 * 1.2in Package weight: 130g / 4.6ounce Packing List: 1 * Mileometer 1 * USB Cable 1 * Mileometer Base 2 * Sponge Gaskets 4 * Sensor Magnet 1 * RubberRing 6 * Fixing Cable 1 * Sensor