Economic package: Compresses cold/heat reusable Com-Four come in a family package to save in three different sizes. They contain high quality gel to keep cold and heat! Hot application: Place the gel compress in hot water at 80 ° C for approx. 4 min or heat in microwave by 45 sec a 280W, then wrap it with a handkerchief and place it in the painful area! Cold application: place the compress in the ice compartment of the refrigerator for approx. 2 hours! Then place the compress in your painful area, relieve your pain!