Here is a post about wire saws, in general.

I should clarify: this is by no means my PSK and it is indeed meant to supplement, not replace. In fact, I already have an orange match vial filled with better matches, except it also happens to have a compass, whistle, etc.

My BoB has an Ultimate Survival Sabercut chain saw which I love and treasure, and which was used to make the cut in the photo shown previously.