The working principle of the sensor: 4 sensor productsthe sensors are installed in the rear of the car, and start when reversing. 6 sensor products:4 installed at the rear of the car and 2 installed at the front of the car. When reversing, turn on all sensors at the same time. The rear sensor is anti-collision and the front sensor is anti-wiping. When driving, brake and activate the two sensors in the front of the car. 8-sensor products:4 in the rear of the car and 4 in the front of the car. When reversing, six sensors are activated, four at the rear of the car and two at the front of the car. When driving, the brakes activate the four sensors at the front of the car. monitor: 1: Display the distance of obstacles in multiple directions 2: Show the distance of the nearest obstacle. 3: Sound alarm. There are three kinds of sounds, mute, buzzer, buzzer + voice, which can be switched by preing the button. 7 levels of volume can be adjusted We are very profeional and know how to make good sensors. We use dual-angle, large-core sensors to avoid false alarms and have a longer service life. If the sensor does not have the color you need, you can choose to shoot the color and spray it yourself Features: 1. Display only start: when the car brakes, trigger car radar, so not to detect obstacles, display does not start. 2. Three voice switch: switch button on the display, three types of alarm sound can switch each other, human voice, buzzer or mute. 3. Smart continue work: 8 probe radar, working in brake triggered when the car radar, when loosen the brake, the radar no power supply at the moment, still can continue to work for 15 seconds. 4. Eight side display: display with eight cursor, each cursor independenty for each probe, intelligent distinction between obstacles. 5. Dual-core work: detection and feedback the information is accurate, fast and avoid the delay of the data. Specifications: Front Sensor Detection Range:0.3M~1.2M Rear Sensor Detection Range: 0.3M~2.2M Rate voltage: 12V DC Rate current: 100mA - 300mA Ultrasonic frequency: 40KHz Control moudle working temperature: -30 - 80 celcius degree Display working temperature: -20 - 70 celcius degree Sensor diameter: 22mm Installation mode: Drilling Sound: Heart beat type, more recent alarm more rapidl Digital LCD display (number & light). Help to provide increased safety for paengers, pedestrians and family members who happen to be around the moving 8-sensor reversing radar list 4-sensor reversing radar list