Foot Warmer
https://www.zhongbangbiotech.com/products/foot-warmer.html

#foot #warmer #not #electric

Main ingredients: Iron powder (exothermic when oxidized), activated carbon (adsorbs moisture and oxygen), vermiculite (insulates heat), sodium chloride (accelerates the reaction), and water.

Reaction process: Upon tearing open the outer bag, the iron powder comes into contact with air to form iron oxide (rust) and release heat energy. The breathable membrane controls the amount of oxygen ent...  more