1、Support alarm function, overspeed alarm, water temperature alarm, voltage alarm, RPM speed alarm. 2、Can be used as multifunctional car meter, can shows vehicle speed, RPM speed, water temperature, voltage, fuel consumption, etc. 3、Plug and play, this head up projector allows you look ahead to get driving information without down head to see dashboard. 4、This OBD HUD can make drivers focusing more attention on road conditions, can enhance your driving safety. 5、Wide application, suitable for most vehicles complying with OBD II standards. Item Type: Head Up Display Material: ABS+PC Color: BlackDial Diameter: Approx. 73mm/2.9in Height: Approx. 82mm/3.2in Thickness: Approx. 23mm/0.9in Compatible: Suitable for vehicles complying with OBD II standards Operating Instruction: Simply connect the head-up display (HUD) with the on-board diagnostic interface (OBD) through the OBD cable, and the head-up display (HUD) will display when the car engine starts. Function: Can shows vehicle speed, RPM speed, water temperature, voltage, fuel consumption, single driving distance, total driving distance, single driving time calculation, clock, engine oil temperature, air-fuel ratio, turbine pressure, brake test, acceleration test, elimination of fault codes, read data stream. Alarm: Overspeed alarm, Water temperature alarm, Voltage alarm, RPM speed alarm Language: Simplified Chinese, Traditional Chinese, English 1 x Host 1 x OBD Line 1 x Base 1 x Double-Sided Tape 1 x Screwdriver 1 x Screw 1 x Manual