Production Review: HUD is short for Head Up Display. It displays driving data on the front windshield such as s peed, RPM, fuel consumption, water temperature, and voltage on the car"'"s front window glass ; avoiding drivers"'" unsafety because of watching the instrument while driving. Drivers can read the driving information instantly, and can always keep the best state on the way with HUD.Product Highlights1: Automatic adaptation models, in line with OBDII or EUOBD models Plug Ready to use (car auto diagnostic system) 2: 3.5"'" L Screen, Windshield Projector, Small but nice 3: Speed Unit KM/H & MPH Switch freely 4: Flexible brightness adjustment. automatic and manual brightness adjustment mode, not dazzling 5: Model design:New tooling design with Sunshine Hood 6: 7 different functions to match freelyChoose your favorite combination 7: Besides the device can work well on OBDII EUOBD standard cars, it can also supports some new hybrid & automatic start / stop cars 8: Accept customization with different MOW Limit: Add Start-up Screen with your logo; Customize Package; Add new functions and display interfaces...M6S HUD FUNCTIONSspeedwater temperaturedriven distancevoltagevoltage alarmwater temperature alarmerror code call the policefatigue driving remindOBD2 EOBD Head-up DisplayWithout turning the head, the mount makes the driver saferSPEED DISPLAYED ON THE WINDSHIELDThe speed is in front of the field of vision SPEEDOMETER ON WINDSHIELDThe speed of the vehicle is displayed on the windshield, no need to look down at the speedSAFE DRIVING80% of accidents are caused by distraction bow your head 3 second=Drive a car 50 meters blindly.Please read carefully before placing an order: 1. If your car is pre-2004 (for US automakers) and pre-2008 (for European/Asian automakers), the protocol is not compatible. can not be used 2. After receiving the package, please test it in your car as soon as possible. If you do not want to keep the device after testing, you can also