Ivy Classic, 28114, 1/4" x 4-5/16" Arbor Pilot Drill, High-speed steel, 118° split point, Precision-ground bright finish, 3 flat sides for set screws, Fits the following: IVY CLASSIC 4H Arbor and 3-1/8" thru 6" Cobalt Advantedge one piece bi metal hole saws.