The Lenox Tools 1779803 4L Arbor with 4 1/4-Inch Pilot Drill Bit for Hole Saws 9/16-Inch - 1-3/16-Inch is a durable, long lasting arbor that works with most hole saws. The 4L Arbor Simply allows you to screw the hole saw onto the arbor. The arbor also allows for you to replace the pilot bits through the use of a hex key and a set screw.