Relief Pak® elastomeric packs are supple enough to contour to the applied location. Pack can be chilled or heated to be used as cold or hot pack. Non-toxic material maintains its pliability even when below chilled below freezing. Pack provides a convenient way to position cold or hot therapy. Tough, flexible gel, specially selected fabric and hook/loop straps provide an exceptionally durable product. Deluxe wrap allows cold or hot to reach the affected areas. Stretch cover allows conformity, heat transfer and comfort. Heat pack in microwave….NOT in water.