Product Material: ABS Size: 4.6 * 4.6 * 1.8 cm Color: Black Display: LCD display Backlight: Green Feature: Wireless automatic wake-up Power supply: 1 CR2032 button battery on the meter head; 1 12V 23A battery for transmitter Quantity: 1 piece Package content: 1 piece * bicycle Odometer 1. The automatic wake-up function automatically wakes up from sleep mode when sensing bicycle vibration. The bright LCD display makes it easy to view driving statistics. 2. Multi functional, small size, light weight, wireless, waterproof design, convenient and durable. This bicycle computer measures speed, distance, and riding time. This is the statistical data that any serious bike enthusiast or fitness enthusiast needs to know. 3. Day and night backlight provides backlight for easy viewing during dark hours. When any button is pressed between 18:00 and 06:00, the backlight will automatically turn on.