Hougen 12220 5/8-Inch Diameter Rotabroach 2-Inch DOC is an accessory for the "12,000 Series" Cutters, to be used on Hougen Portable Magnetic Drills and materials up to 275 BHN. This M2 HSS Cutter features a 3/4-inch diameter shank, and is made of hardened, high speed tool steel and precision ground. The 5/8-inch cutter diameter is to be used with pilot 10534 and has a decimal equivalence of .6250.