I work for a Police Department and the fire dept gave us a bunch of cutters designed to cut seat belts. The problem with knives is that if your in a position to need to cut the seat belt, it may be a little tough to operate a lockblade knife and cut away at the seatbelt. I think that the tool we have is a protected blade type that would reduce any accidental cutting. I think that you can get these from Gall's magazine. Also, just FYI. any swithblade, butterfly or knife over 5 1/2 inches long is illegal to carry. Its a class A misdemeanor. (not that I care
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Todd