I just found a Jon-e handwarmer my Dad used to use when hunting. It is a re-usable metal handwarmer that goes in a cloth sack after it is lit. It is similar to the old Zippo lighters and if I remember correctly, it is filed with lighter fluid. It has a wick that is lighted and its glowing flame simmers to keep your hands etc. warm. I would like to try it, but would like confirmation that it is in fact lighter fluid that is used to burn in it. ANY HELP?