JH-Installs Front and Rear Park Assist System with 4 black sensors and LED Display (optional extra) with adjustable volume. The system warns user by acoustic signals. Dual intelligent functions for cars with tow-bar, spare wheel or other protrusion. New functions of sensitivity setting and learning function added. Perfect performance under heavy rain environment. Set includes 4 pieces of ultrasonic sensors, control unit, LED Display (optional extra) and wiring. The unit is for vehicles with 12V DC only.