Car parking sensor consists of ultrasonic sensors, digital control box, camera and led/lcd/tft display. This system detects the distance between the car and back obstrusction with ultrasonic sensors installed at the rear bumper of car. The obstruction image will be shownvia the camera. With the change of alarm sound, detect the safe area correctly. It is best choice for the safe of your car. Features:- more features, small volume & lightweight. Can simultaneously observe the three sets of data stream. 4 sensor system, double cpu and advanced chipset for enhanced coverage and detection.4. With digital colored led display (number & light).Bi bi bi alarm prompts step by step, the closer the obstacles, the louder and faster the sound alert. Help to prevent dangerous and costly collisions. Help to provide increased safety for passengers, pedestrians and family members who happen to be around the moving vehicle detect small children and low walls as wellanti-freeze and rain proof. Easy to install specification :- rate voltage: 12v sensor color ff1a;silver operation voltage range: 9v - 16v rate current: 20ma - 200ma detecting distance: 0.3 - 2.5m ultrasonic frequency: 40khz working temperature: -30 - 70 celcius degree display working temperature: -20 - 60 celcius degree led display size: 10 * 2 cm main control box size: 9 * 6 * 2.3 cm main control box weight: 50.2g package contents :- 1 x main control box 1 x led display indicator 4 x parking sensors with 2.5m line 1 x hole saw 1 x power cable 2 x double side sticker 1 x user's manual