When was the last time you practiced starting a fire FROM SCRATCH with just a Ferro Rod, striker and some tinder?
A good Ferro Rod and Striker, like this one from County-Comm, is worth it’s weight in gold.
I also keep a sandwich bag full of dryer fluff (that stuff on your dryer filter) stuffed inside a couple of cardboard toilet paper rolls for tinder in my GO-Bag. If available, it’s also smart to keep some lighter pine handy with your tinder.