1/8", 3/16", 1/4", 5/16", 3/8", 7/16", and 1/2" plus hex wrench
Oxide steel stop collars use hex screws (wrench included) to tighten the collar around the bit
Editor Reviews:
Product Description: The steel stop collars use hex screws to tighten the collar around the bit, rather than locking into the flutes so they are less likely to loosen or damage the flutes