1. HUD Digital Speedometer: Head up display gives you realtime feedback on your speed through GPS, and the headup display design allows you to avoid looking down to read the instrument, ensuring r driving. The GPS head up display is equipped with a 5inch LED screen to clearly display the data. In addition, the digital speedometer is equipped with a light sensing system that can automatically adjust the brightness for easier reading. 2. Multidata Heads Up Display: Besides being a digital speedometer, our car heads up display can show a variety of data: Time, Driving distance, acceleration time, latitude and longitude, altitude, etc. The heads up display has various data modes for you to choose from, enabling you to zoom in on the data you need more precisely. Moreover, the heads up display can switch between MPH or KM/h. It's a good driving assistant. 3. 2 Alarm Functions: The car gps speedometer is equipped with three stages of speeding alarm and fatigue driving alarm. The initial default values of the car gps speedometer for speeding alarm are 150KM/h, 180KM/h, 200KM/h, and the initial default value of the fatigue driving alarm is: alarm after 8 hours of continuous driving. Both alarm functions of the car gps speedometer can be adjusted to meet needs. These two alarm functions can improve your driving factor. 4. For 5V Vehicles: The car heads up display operates at 5V. As long as your vehicle has a 5V USB port, the car heads up display is compatible with your model. It's easy to install, plug and play. Just connect the USB of the gps speedometer to the USB port of your car, and the car heads up display will automatically switch on and off with the car ignition, without worrying about power waste.