Features: 100% brand new and high quality It can provive increase safety for you and your family,it also can prevent dangerous and save the collision cost. Accurately detect the position and distance of obstacles. Parking sensors are proximity sensors for road vehicles designed to alert the driver of obstacles while parking. These systems use either electromagnetic ultrasonic sensors. Rear sensors may be activated when reverse gear is selected and deactivated as soon as any other gear is selected. Detection distance: 0-2.5m.