Features: Used to measure speed, distance and driving time. Small size, light weight and fashionable design. Wire-less design, more convenient to use. LCD digital display is convenient to read the data. Waterproof, you don't have to worry about the rainy day. Suitable for all types of bicycle, such as road bike, mountain bike, folding bike, common bike and so on. Specifications: Material: ABS Funtions: Setting Speed Scale (km/h) / (m/h) CLK Clock (12H/24H) Setting the Last value of Odometer Speedometer Speed Comparator ODO Odometer (0-9999km/m) MXS Maximum Speed AVS Average Speed TM Trip Time Sleep Mode Power Supply: AG13 Button Cell for Speedometer (Included) 23A Alkaline B-attery for Transmitter (Not Included) Package Size: 100 * 70 * 30mm / 3.94 * 2.75 * 1.18in Package Weight: 100g / 3.53ounces Package List: 1 * Speedometer 1 * Transmitter 1 * Base 1 * M-agnet 1 * Nylon Band 1 * Button Cell 1 * User Manual Note: 1.Due to the different display screen and light effect, the actual color of the item might be slightly different from the color showed on the pictures. 2.Although the speedometer is waterproof, please avert being exposed to rain and water for a long time as it can penetrate. 3.The distance between sensor and bicycle computer should not be more than 500mm, and the sensor and m-agnet not more than 3mm, or it cannot signal the signal. LCD digital display is convenient to read the data. Wire-less design, more convenient to use. Waterproof, you don't have to worry about the rainy day.