Whole nuther thought. A Buckaroo pouch or folding knife pouch has been popular in the cowboy world for many years. Lots of the advantages of a slip with a clip and none of the disadvantages. No clip to scratch the paint of your buddy's truck as you are putting the ice chest in the back, no clip to get caught and snagged and stretched out, no clip to get tangled in a seat belt, no clip to wear your pocket out, no clip to scratch the furniture etc. It back threads on a belt loop and can go in either a front or back pocket. Need your knife, tug on the thong and the pouch comes out of the pocket. Leave the pouch hanging while you use your knife and then tuck it back in when done. Works for a lot of folks.
Getting to work:
Something to consider maybe.