Excelvan A8 5.5" Car HUD Head Up Display with OBD2 EOBD Interface Plug & Play KM/h MPH Speeding Warning Fuel Speedometers HUD (Head-Up Display) projects driving data without requiring drivers to look away from their usual viewpoints HUD automatically adjusts its brightness level, so its projections are clearly visible in direct sunlight or at night. Alerts you if you exceed the speed limit by setting Over-speed buzzing alarm 5.5 inch LCD display, portable and easy for drivers to read data Projects a lot of driving information onto a transparent film on your windshield such as speed, over speed alarm, engine rpm, water temperature, voltage, instant fuel consumption, average fuel consumption, mileage, shift remind, fatigue driving remind, undervoltage alarm, high water temperature alarm, engine failure alarm, KM/MILE free shift, etc.