Gives comfortable continuous heat for up to 24 hours (12 hours for Jr. model) on a single filling. These heat generating pocket sized warmer are great for anybody who spends time in the cold. Platinum catalyst flameless technology ensures easy lighting and stable temperature from beginning to the end. Made of polished chrome plated copper, which does not rust like steel. It includes a carrying case and an extra heating element. Buy one for each pocket or coat and never be chilled in the cold again. The Xtreme Gadget hand warmer is the ideal gift for the hunter and fisherman, and anyone that enjoys the outdoors in the winter. The hand warmer can also be used in the event of an emergency and should be part of every winter survival kit. This is probably the best hand warmer in the world. Xtreme Gadget is currently the only company selling this type of flameless warmer in America. The other types of hand warmer are disposable (expensive, relatively short heating time, too small to keep warm for a large hand) and the reusable type (hot to cold in only 1 hour, need to wrap it in towel to boil in water for 15 minutes to recharge). This is the best and most elegant type of hand warmer.