IVY Classic Industries is dedicated to producing a comprehensive, quality line of power tool accessories and hand tools. IVY Classic Arbor Adapters are designed to adapt 1/2-inch - 20 thread arbors to fit 5/8-inch - 18 thread hole saws. The hex flange allows for easy installation and removal. These arbor adapters fit IVY Classic arbors 28100, 28103, 28104, 28105, 28108, as well as other 1/2-inch - 20 thread arbors.