Package Included: 1 x Head Up Display Please note that: B3 style is OBD system G3 style is GPS system B3 OBD HUD Functions: vehicle speed, tachometer , water temperature, fuel consumption, voltage, time, single driving distance, single driving time Alarm: overspeed alarm, speed alarm, water temperature alarm, voltage alarm, fatigue driving reminder alarm G3 GPS HUD Functions: Functions: vehicle speed, clock, compass, single driving distance, driving time, number of satellites, altitude, and acceleration time of 100 kilometers Alarm: overspeed alarm, fatigue driving reminder alarm Note: 1. The OBD head-up display is only suitable compatible for gasoline vehicles. 2. Gasoline vehicles with OBD2 agreement produced in the United States after 2004, and gasoline vehicles with OBD2 agreement produced in other regions after 2008 can be used. However, some cars still cannot be used, please