SD-10: (10 Hole Sizes) Two Flutes 3/8" Shank
1/4", 13/32", 9/16", 5/8", 11/16", 3/4", 13/16", 7/8", 15/16", 1"

Evolution Premium Step Drills are made from the same high-quality M2AL as Cyclone Premium Annular Cutters. These tools are heat treated to 68RC, giving them more durability during tough applications.

Evolution Premium Step Drills are used to produce a range of hole sizes in steel up to 1/8" thick using only one tool. The twin flute design allows for a smoother cutting action with no pre-drilling necessary. Evolution Premium Step Drills have 3 chucking flats on the driving shank to ensure no slipping in the chuck.

Diameters

SD-6: (6 Hole Sizes) Two Flutes 1/4" Shank
3/16", 1/4", 5/16", 3/8", 7/16", 1/2"

SD-9: (9 Hole Sizes) Two Flutes 3/8" Shank
1/4", 5/16", 3/8", 7/16", 1/2", 9/16", 5/8", 11/16", 3/4"

SD-10: (10 Hole Sizes) Two Flutes 3/8" Shank
1/4", 13/32", 9/16", 5/8", 11/16", 3/4", 13/16", 7/8", 15/16", 1"

SD-11: (11 Hole Sizes) Two Flutes 3/8" Shank
1/4", 25/64", 35/64", 11/16", 13/16", 7/8", 1", 1-1/8", 1-7/32", 1-1/4", 1-3/8"

SD-12: (12 Hole Sizes) Two Flutes 3/8" Shank
3/16", 1/4", 5/16", 3/8", 7/16", 1/2", 9/16", 5/8", 11/16", 3/4", 13/16", 7/8"