If you're out in the wilderness at night and it's starting to get chilly, you sure as hell better know how to make yourself a campfire. But let's just say you forgot your matches and don't feel like rubbing two sticks of wood together hoping to create a spark.
If you have a 9 volt battery with you and some steel wool you can just as easily create a spark and start a fire. Technically you need at least a D battery, but a 9 volt works best.
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