Morse, AV36, Hole Saw, Heavy Duty, Series: Master Cobalt, 2-1/4 in Diameter, 1-1/2 in Cutting Depth, 5 TPI, 5/8-18 Arbor, 1/4 in Dia x 4-5/16 in L, 1/4 in Dia x 3-1/16 in L Drill, M3 HSS Cutting Edge, Bi-Metal Body, Positive Rake Cutting Edge, Use Arbor: M35PS, M45, M45P, M46PS, M55P and M44K, Applicable Materials: Wood, Plastic, Machinable Metal, Stainless Steel Alloy and Nail Embedded Wood