This 13 piece Hole Saw kit is designed specifically with the needs of Plumbers and Electricians in mind. It includes all the sizes you need everyday in an impact resistant plastic carrying case. Hole Saw Sizes are: 3/4 inch, 7/8 inch, 1-1/8 inch, 1-3/8 inch, 1-1/2 inch, 1-3/4 inch, 2 inch, 2-1/4 inch, 2-1/2 inch. Arbors 1/4 inch round shank for 9/16 to 1-3/16 hole saws, 7/16 hex shank for 1-1/4 to 6 inch hole saws. Pilot drill. Arbor adapter and spacer. Hole Saws are 4/6 tooth design for more efficient chip clearance and less heat build up.