Good2Go Medium 9 x 12 Plush multi-ply cover design focuses moist heat right where you need it most Joint-specific or multi-use shapes for a snug secure fit Portability convenience and economy in a reusable unit that will last for years Patented non-allergenic fill does not leak smell decay or encourage fungus growth Fill has a special porous surface to trap the maximum amount of atmospheric moisture Wide elastic strap holds heat snugly in place while you continue regular activities Mitt is filled with two soft gel-packs that can be heated or frozen as needed to surround your hand with either hot or cold therapy