Autosessive supply the Park Safe 4 Eye Parking Sensor Kit.
This parking sensor kit has an audible buzzer, mounted inside the rear of the vehicle which starts sounding at 3 beeps per second when the object is closer than 1.67 metres to the ear of the vehicle. As the vehicle gets closer to the object the beeping frequency increases from 5 to 8 beeps per second. When the vehicle is about 30cm from the object the beeping becomes constant. As a result, the driver always knows exactly where the bumper is positioned in relation to an object. This parking sensor kit is powered off the reversing lights circuit in the vehicle so is only activated when reversing.