A magnesium fire starter with a ferrocerium striker and tinder cord wrapped around the handle.

The reason a striker beats a lighter in an emergency is that it does not care about being wet, cold, empty or at altitude. Scrape it and you get sparks at a few thousand degrees, every time, for years.

The catch has always been tinder — sparks are useless without something that will take them, and in the rain there is nothing dry on the ground. The tinder cord solves that: it is wound onto the tool, so the fuel and the ignition arrive together.

Shave a small pile of magnesium, fray a short length of cord onto it, and throw sparks into the pile.

Practise once in the back yard. Striking a ferro rod is simple and completely unobvious the first time.