Feature: 1) Very Easy Installation, NO cable connection between control unit and display. 2) Display type: LED Display 3) Sensor number: 4 4) Sensor color: black, red, white, silver, green, gold, orange, blue 5) Detector type: adhesive or built-in 6) 3-digital distance display 7) Activation: a) Rear sensors are activated when reverse gear is engaged b) Obstacle distance will be shown on the display c) When you are backing the car, the rear sensors will detect obstacles behind the car automatically d) Stage-by-stage sound alarm to avoid collisions with adjustable volume and mute setting 8) Versatile detection range 9) Various of sensor types available to choose from Specifications: 1) Working voltage: DC 12V & 24V 2) Static current: 40mA 3) Beeper: 60dB 4) Working temperature: -30~+80oC 5) Frequency: 40kHz 6) Best detection distance: 0.4m ~ 2.0m