Product Description Material: ABS Size: 4.6 * 4.6 * 1.8 cm Color: Black Display: LCD display Backlight: Green/White Features: Wireless automatic wake-up Power supply: 1 CR2032 button battery on the measuring head; 1 12V 23A battery for the transmitter Quantity: 1 pc Package content: 1 pc * Bike computer 1. Automatic wake-up function Automatically wakes up from sleep mode when vibration is detected in the bike. Bright LCD display for easy viewing of riding statistics. 2. Multi-functions Small size, light weight, wireless, waterproof design makes it convenient and durable. This bike computer measures speed, distance and riding time. Just what a serious cyclist or fitness enthusiast needs to know to track statistics. 3. Day and night backlight Provides backlight for easy viewing during dark hours. The backlight turns on automatically when any button is pressed between 6:00 PM and 6:00 AM. Please note that the slight rattling from the device is a normal phenomenon due to the design of the wireless automatic function. 4. Easy to install and use Easy installation that takes a few minutes. Simple navigation interface with only two buttons to access all measurements. Adaptable to most common tire sizes for accurate statistics tracking. 5. Applicable Road bikes, mountain bikes, folding bikes and other common bikes are compatible with this bike computer. This bike computer may not be compatible with some electric bikes. If the computer screen, sensor and magnet can be installed within the specified distances, the device should be fully compatible. Please feel free to contact us if you have any questions.