Great compatibility: this head display is gps + beido dual-mode chip. it is compatible with all vehicles around world. refresh rate is 10 frames per second, and speed of car changes smoothly and continuously. two alarm functions: it supports overspeed alarm and fatigue driving alarm. over speed alarm setting is 30-250km/h. head display will alarm when vehicle speed reach to setting value. fatigue driving alarm setting is 1 to 8 hours, head display will give fatigue driving alarm when your continuous driving time reach to setting value. gps compass: it can dispay all directions, e(east), w(west), s(south), n(north). display function: this head display can diplay speed, driving mileage, compass angle, satellite icon. plug and play: use usb cable to collect lighter.
