The Ultrasonic Leak Detector (ULD) is a hand-held, high quality instrument that can locate costly leaks ina compressed air system. A person using the ULD need only aim it in the direction of a suspected leak. When a leak is present, an audible tone can be heared with the use of the headphones, and the LED dispaly will light. Testing the various unions, pipes, valves and fittings of a complete installation can be done quickly and effectively at distances up to 20' (6.1m) away! Plants that aren't maintained can easily waste up to 30% of the compressor output through leaks that go undetected. Saving the wasted compressed air reduces overall operating costs