12 hole sizes: 3/16" (4.76mm), 1/4" (6.35mm), 5/16" (7.94mm), 3/8" (9.52mm), 7/16" (11.11mm), 1/2" (12.7mm), 9/16" (14.29mm), 5/8" (15.88mm), 11/16" (17.46mm) , 3/4" (19.05mm), 13/16" (4.76mm), 7/8" (22.22mm) with 1/16" (1.59mm) increments. The size marks are stamped next to each step to ease the use.
double spiral flutes for more efficient swarf clearance; 1/4 Inch hex Shank with quick release slot to eliminate slipping; Self-starting for clean holes in thin materials;
M35 cobalt HSS to cut stainless steel. The step drill bit is made with M35 cobalt. It is ideal for variety of materials from stainless steel, metal, plastic, fiberglass to wood. They also help to enlarge existing holes. M35 HSSCo is a high speed steel alloy made up of 5% cobalt. M35 is similar to M2, but with 5% cobalt added.
The addition of cobalt increases heat resistance. It is widely used in metal manufacturing because of its ability to resist wear over conventional high speed steels, allowing for shorter cycle times in production environments due to higher cutting speeds or from the increase in time between tool changes. M35 is also less prone to chipping when used for interrupted cuts.