Besides carrying a Bic lighter and a fire steel on my key fob, I also have devised a little "fire tube" to keep some of the essentials in.
I have taken 2 Papermate Flexgrip pens (cap style) and removed the writing end and replaced it with the the other top end from the second pen. It no longer serves as a pen but I have found that I can put cotton balls, a ferro rod pried from a magnesium bar and some pre-shaved magnesium flakes all inside.
Open the cotton ball end, remove cotton ball (you might have to pick at it a bit to get it out), pour some magnesium from the other end onto the cotton ball, strike with ferro rod, (you are carrying a knife aren't you?
) and hopefully POOF!
You can even use the pen cap to help carry it in your pocket.
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