I used to carry one, but I don't anymore. When I did, it was a mini-Bic. I took a very small piece of duct tape and rolled it onto itself, making a tight roll about the thickness of a pencil lead. I then cut this down to a small length so that I could bend it into a "U" shape and put it under the gas switch (or whatever you call that part you depress to release the gas). Then I took another small piece of duct tape and put that over the side of the gas switch, holding that "U" in place so the switch wouldn't be accidentally depressed in my pocket. Next, I took two large rubber bands (cut from bicycle inner tube) and attached the mini-Bic to a P-51 can opener (or was it the P-38? ... whichever is the larger of the two). Then the P-51 was attached to my keyring with a small split ring. Kind of a hokey setup, but it worked. And I had the can opener and ranger bands as bonus pieces of equipment.