HotHands Hand Warmers (Box 40 Sachets) Warmers are single use air-activated heat packs that provide everyday warmth and are ideal for keeping your hands warm when the temperature gets cold. They provide safe, natural heat, so you can enjoy the great outdoors during those harsh winter months. Our hand warmers are designed to fit in your pockets or the palm of your hand. Convenient, Compact, Portable. Thoughtfully designed so you can enjoy anytime, anywhere.