... display&rear 4 sensors 3.BiBi-alarm sound or voice 4.CE,FCC,e-mark,RoHS parking sensor : LED Parking Sensor System details ... ,Display unit with built-in buzzer 6,2,3,4 sensors for option 7,Display size: 132*25*22mm LED Parking Sensor System ... figure. 5. Easy installation. 6. It can be paired with wireless parking sensor, no need to run a wire from the front ...