Hot water bottle bags are made from rubber that could withstand sufficient heat. Packs filled with hot water and sealed with a stopper can be carried and provide warmth. Available in stock colors.Packaging:1. One pc in a oppbag.2. One pc with a color peper packing card in a oppbag. 3. One pc with your own design of knitting bag cover.4. One pc with your own design of polar fleece bag cover.