I made a cunning webbing loopy thing that the clipper sheath fits snugly in, and provides it with a secure belt loop, as well as a Velcro retention strap over the knife handle. I'll try and put a picture up- but it involves several lengths of olive webbing, a short bit of elastic, and some velcro. Very simple to knock up on a sewing machine.
Every survival camp we take the scouts on, we seem to spend at least an hour trying to locate lost clippers. The problem with the sheath is that it tempts people (well scouts!) to clip it to places even less secure than a belt- like pocket flaps etc.
