Features: Real-time update of vehicle speed to avoid violations. After installation, elevate-the visible vehicle-condition, without frequent viewing of the central control screen, to avoid accidents. Energy saving, automatic shutdown after flameout (starting and closing with the central control, automatic shutdown). Intelligent chip, real-time synchronization with central control data.Head up display, safe driving, on-board original data, non-destructive installation, the air outlet can be moved at will. Speed alarm, fatigue driving reminder function, improve driving safety. Specifications: Material:ABS Size: Approx.7.5x1.7cm/2.95x0.66inch Color:Black For 3 Y Package Includes: 1x Car HUD note: ①.Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. ②.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thanks for your understandings.