Ulincos Reversing Parking Sensor LED Display U5800 Car Roof Mount Mirror Image Displayed Vehicle Rear Parking Assist System with 4 Sensors (Black) Mirror image displayed, the display can be fitted on the back side of roof and can be viewed from rear view mirror Three Colors LED digital display shows the distance between the car and obstacle High-volume warning buzzer with ON/OFF key, closer the distance the alarm sound is shorter and rapider Prevent costly collisions and help to increase safety for passengers, pedestrians and your family Enhanced CPU and advanced 4 auto detector sensors. 4 sensors are anti-freeze, waterproof, and quakeproof