Features: 1) Display type: digital LED small or broad display 2) Sensor number: 2 - 4pcs 3) Sensor color: black, red, white, silver, green, gold, orange, blue 4) Detector type: drilling or stick-on 5) 3-digital distance display 6) Activation: a) Rear sensors are activated when reverse gear is engaged b) On backing the car, the rear sensors detect obstacles behind the car automatically c) Stage-by-stage sound alarm to avoid colliding 7) Versatile detection range 8) Sensor types for optional Specifications: 1) Working voltage: DC12V&plusm;2V 2) Input: 5W (max) 3) Beeper: 80 - 95dB 4) Working temperature: -40 ~ +80oC 5) Frequency: 40kHz 6) Best detection distance: 0.3 - 1.5m Outer packing: 10pcs/carton Carton dimensions: 34 x 21.5 x 39.5cm