US Patent 6893453 Thermal therapy pad with variable heat control

There is provided a thermal therapy pad useful in relieving pain and having a plurality of easily removable layers on the side of the pad normally facing the skin. The removal of layers results in increased heat removal or delivery to the skin. The removable layers may be re-attached desirably the user find the pad too hot, or may be moved to the opposite side of the pad, or discarded. The pad may use an iron powder reactive core which reacts exothermically with air to provide heating or water and other reactants that react endothermically. More than one core may be used to further tailor the amount and rapidity of the temperature change.