Seems a bit bulky, may leak if not treated with Teflon tape and I would guess it may be very hard to open up when the caps been on a while and or when your hands are half froze.
I make these homemade fire starters that are completely self contained; they are waterproof, have a striking surface that works on most everything (no need for a lighter or matches to get them going) They burn for several minutes allowing you to get your tinder going, they are easy to make and take up very little space. The only drawback is that they are wax-coated and may get wax on other things if left in a hot car. I solve this problem by keeping them in a zip-lock bag.
Here is a picture that shows one of them, it’s at the bottom of the picture under the stove.
All it takes to make them is some cardboard, strike anyplace matches and an old cooking pan (Goodwill store $2.00) to heat wax in to dip the cardboard in.