1. Head-up display of driving speed. 2. Driving time and mileage calculation and display. 3. Over-speed alarm setting. 4. Fatigue driving alarm. 5. Altitude display. 6. Local time display with auto timezone adjustment. 7. Easy setup – Plug & Play – Power through vehicle lighter. No professional installation required. 8. Compatible with all cars and trucks. Uses GPS signal guided calculation. No wiring needed to the VSS (vehicle speed signal). 9. Display in MPH or KM/h. 10. Auto adjust brightness through sensor for day and night driving. 11. Green color data display, easy on the eyes. 12. Total mileage display after car stops. Parameters: 1. GPS positioning time: 1 to 5 minutes in open air (weather may affect positioning time). No GPS signals indoors. 2. Speed deviation: Since speed data comes from GPS satellite, slight deviation is unavoidable. 3. Input voltage: DC 5V. Input current: DC 50–120mA. Working temperature: -30 to 70 degrees Celsius. 4. Driving data deviation is around 2%. 5. All driving data will be cleared when powered off, except total mileage. Color: Black Material: Plastic Package Contents: 1 x HUD Only the above package content; other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture to appear slightly different from the actual item. Measurement allowed error is +/- 1–3 cm.