I keep a Houdini Rescue Tool in my truck; it's attached to a paracord loop around the steering column. The Houdini is hard to separate from the lanyard loop but one good tug and it pops off (with the other end secured, that is). The nice thing is the loop is way too small to slip over the wheel so it has nowhere to go in the event of a rollover, etc. It has a belt cutter and a glass breaker, and I've tested both to be sure they work.