Shank Arbor with High-Speed Steel Pilot Drill Bit in Clamshell. 5/16" shank, 3/8" minimum chuck size. Use with 9/16" - 1-3/16" Hole Saws. The best arbor in the industry ensures a solid connection without any gaps or wobbling. Arbors include replaceable, high-speed steel pilot drill. Pilot drills hav