Triple:

Take the opposite side one out, and go to the hardware store for a match. Shouldn't cost ya more than 5o cents. Heck, if you are prone to loosing 'em, get a few. But it might be easier to use a bit of the easy-repease locktite, or a cheap sub, Shoe Goo. Rub a bit on the threads before you screw it in. DON'T use CA as locktite... you'll have to use MEK or CA debonder to get the thing out...