Features: *1. Widely Used: Powered by a 5V USB or cigarette lighter power supply, it can work on all cars/trucks/buses/electric vehicles, etc. *2. Plug and Play: After connecting to the power supply, it works directly without any other operations. When you start/stop the engine, the Head-up display turns on/off automatically. *3. Accurate Speed Monitoring: no jumping speed. GPS+Beidou dual chip ensures real-time and accurate vehicle speed monitoring and display. *4. User-friendly Display Screen: equipped with a lens hood to block sunlight, and large font clearly displays key data day and night. *5. Speed Unit: km/h and mph two unit versions; This device is a GPS digital speedometer, and the speed is collected from satellites. Therefore, if tested at home or in a parking lot, the speed may not be displayed correctly. Please test outside the vehicle with good signal. *1. Power Supply: car cigarette lighter/USB *2. Display Screen Color: white/green *3. HUD Size: 79x46mm Package Includes: 1 x HUD 1 x Power Cable 1 x Manual