Greenlee 645-011 Quick Change Arbor for Sizes 5/8 Through 2-1/4-Inch, 3/8-Inch Shank Cuts stainless steel quickly and easily Quick change arbor allows you to change cutter heads with a simple push and a turn Use the same arbor for different size cutting heads Flange stop prevents over-drilling Replaceable, cobalt-steel pilot drill with split-point tip to prevent walking