I messed up a collet on my DeWalt compact router because the shank was less than 1/4" diameter. Since the collet was slightly smaller than the collet, it was fully tightened, but not in contact with the shank of the drill, and the drill simply fell out, and of course the jaws of the collet did not return to normal, only destroyed it. Replacing the collet costs $25. I send mine back and get a trademark like Freud or Bosch. Don't buy cheap if you can't see the item first. Thank goodness for Revane's guarantee!