Introduction: Rock Hand Warmer
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About: I'm still working on my electronics skills. If you see a flaw in any of my crazy plans, feel free to let me know!
These hand warmers are great to stick in a cold coat pocket. You just grab a rock, clean it off, stick it in the oven, wrap in foil to control the loss of heat, then put it in your pocket. I like to use them on camp outs, except you put it over the fire there.
