1Reflect Information: The main function of the Hud display is to reflect the information of the car dashboard, such as vehicle speed, Rpm, water temperature, voltage, travel distance, etc. 2Ensure Driving Safety: OBD2 smart gauge can keep the driver's eyes on the road all the time, no need to look down to read the instrument, avoid danger and improve driving safety. 3Multi Function Meter: OBD2 system is multifunctional, it can display vehicle speed, engine speed, water temperature, voltage, fuel consumption, altitude, clock, driving time, driving distance, number of compass satellites. 4Alarm Function: Car Hud speedometer is really safe to use, it has overspeed alarm, speed alarm, water temperature alarm, voltage alarm and fatigue driving reminder. 5Plug and Play: This car Hud display comes with 1 cable, OBD2 cable, just plug it in and you can use it and modify your car, convenient to use.