ULTRASONIC LEAK DETECTION is the preferred method to ensure a leak-free installation. Our ULF481 - Ultrasonic Leak Detector provides a simple and professional process that will save you time while ensuring the accuracy of your replacement. By placing the transmitter inside the vehicle, the sound waves will transmit through the headphones when you run the receiver over the pinchweld area. The sound waves will not go through glass, rubber, or metal and will register a louder tone when a leak is detected. In addition to the audible sound, the receiver features a light that changes from green to red if the bond is not secure in an area. Solve the problems before they start, and order yours today.