When iron oxidizes it produces iron oxide, more commonly referred to as rust. The salt acts as a catalyst. The carbon helps disperse the heat. The vermiculite is used as an insulator for the purpose of retaining the heat and the cellulose is added as a filler. All of these ingredients are surrounded by a polypropylene bag.
Polypropylene allows air to permeate the ingredients while holding in moisture.
Due to the size of the Japanese market there are many manufacturers of this product that compete for a piece of the pie. The U.S. market is supplied by numerous importers who source their products from some of the many manufacturers in Japan. Always having product on hand to sell is as important as having the lowest price. We are members of The Conservation Alliance and Leave No Trace. The North American Hunting Club and North American Fishing Club have also given us their seals of approval.