Ultrasonic welding is an industrial technique which makes two pieces of plastic or metal be joined together seamlessly through high-frequency acoustic vibrations. One component to be welded is placed upon a fixed anvil, with the second component being placed on top. An extension connected to a transducer is lowered down onto the top component, and a very rapid, low-amplitude acoustic vibration is applied to a small welding zone. The acoustic energy is converted into heat energy by friction, and the parts are welded together in less than a second.