Storage compress: The Gel Bag for cold and heat therapies comes with a large double size package. The cool-pack is filled with high quality refreshing gel cold application: place the compresses in the freezer for 2 hours. The gel bags remain flexible to -21 degrees and adapt perfectly to the area to be treated. Hot application: place the gel compress in hot water at 80 ° C for 6 minutes or heat it in the microwave for 4 minutes to 280 watts, Then place the gel compress in the protective case.