TheraBeads provides therapeutic moist heat to treat arthritis, minor muscle aches, pains and sprains. The hygroscopic beads in every TheraBeads product have a coating that enhances their ability to capture moisture. Simply heat the pad in the microwave for under two minutes and place it on the affected area to experience the deep penetrating qualities of the retained moisture from the beads. There is no water or cord required. TheraBeads are ideal for the shoulders, knees, neck and back. They are designed to conform to any part of the body, providing a soft, snug fit. Measures 9? by 12? and includes a wrap cover.