Water activated, each heavy duty bag will heat several retort pouches. Remove retort from box and put into heater bag, add water and close bag, in 10-15 minutes you have a hot (about 140?§F) meal. MRE heater bags must be used with caution. DO NOT USE THE WATER after you have activated the heater. Do not re-use heater. Please dispose of properly. DO NOT USE IN A SEALED ENVIRONMENT, leave some ventilation. An excellent way to get a hot meal even in the harshest of conditions. Used by armies around the world for troops in the field. 12 heaters to a pack.
NOTE: Double sealed in plastic. Take Extra care, DO NOT STORE WITH LIQUIDS that might accidentally activate the heater. Keep out of reach of children