Hothands warmers are single-use air-activated heat packs that provide everyday warmth and are ideal for keeping your body warm when the temperature gets cold. Available in several styles designed for hands, feet, and body. Hothands contain ingredients like iron, activated carbon and water. Once the ingredients come into contact with oxygen, they oxidize, producing heat. The combination of ingredients has been specially formulated to ensure a constant and comforting heat for a wide variety of uses. Up to eight hours or more of long lasting heat. Ready-to-use. Air-activated. Safe, natural heat. Single-use, heat packs provide additional warmth.