I lost the Allen wrench for the crimson trace grips on my 640 and CT had shown them out of stock for quite some time now. The smallest in any of my sets is a .050" and it was too big. I looked online and found that NAPA has them in the correct size, .028". I went to the store to pick it up and found I nearly need a magnifying glass to see the darn thing! I think I'm going to superglue it or solder it to something to make it harder to lose and to get a better grip on it. Anyway, if any of you misplace your adjustment tool, NAPA has them for $1.29+tax.