I taught a class on this at our Winter FTX . If you are considering binary components (i.e. 9v and steel wool) you're alot better off with potassium permanganate and antifreeze. Makes a hell of a flame as an exothermic reaction. Plus pp can be used to make an astringent solution or purify water.

Though I have seen bonfires started in the pouring rain with a road flare.

'In the hour of need, at the moment of truth; you will not rise to the occasion - you will default to your level of training' -LtCol Dave Grossman

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