The Starrett XA2 Quick Hitch Arbor with 6.35mm (1/4") carbide tipped pilot drill and 11mm (7/16") hex shank, fits hole saw diameters 32-210mm (1.1/4" - 8.9/32"). A set screw in the body allows for easy replacement of the pilot drill. Quick Hitch arbors permit instant change of hole saws without tools or removing the arbor from the chuck.