Heat Factory Large Size Body Warmer Big Pack 10 Units. This Hand and Foot Warmer from the experts at Heat Factory is a soft lightweight pouch containing a biodegradable mixture of iron powder charcoal salt sawdust and vermiculite. When exposed to the air a chemical reaction takes place that generates heat. The Heat Factory Case of Body Warmers have an unopened shelf life of three years or more. This Heat Factory Heat Generation Pack is made using incredibly durable materials that ensure a long lasting and efficient product. For a perfect way to assure you always have an adequate heat supply purchase the Heat Factory Body Warmer Case Pack. Specifications for Heat Factory Large Size Body Warmer Big Pack: Manufacturer: Heat Factory Additional Features: 10 Units Size: Large Features of Heat Factory Large Size Body Warmer Big Pack: 10 units Case pack = 24 units Package Contents: Heat Factory Large Size Body Warmer Big Pack Heat Factory 19642: Large Size Body Warmer Big Pack 10 Units