Hanson Step Drills save time by eliminating the need to change drills when drilling round holes in thin materials. Each smaller size drill also acts as a pilot for the next size. The single radial flute assures perfectly round holes. Use on steel, brass, aluminum and other thin materials. Step Drills are self-starting and will not slip.Drill diameters etched in flute for easy identification.
From the Manufacturer
The #2 UniBit Step Drill has 6 holes--3/16-inch to 1/2-inch hole sizes with increments of 1/16-inch; shank size is 1/4-inch. Each UniBit step drill has an easy-to-sharpen, non-skid tip which eliminates skidding and the need for center punching; the tip gives sure starts even on curved surfaces. The single-fluted cutting edge that you will find on the UniBit step drills helps assure true round holes and allows greater control. They are constructed of industrial grade high speed molybdenum steel and heat treated to assure maximum durability. The UniBit step drill has 3 flatted shanks, which prevents slipping in drill chuck. The multiple steps on each UniBit eliminates the need to maintain a toolbox full of specific size drill bits. Full lifetime warranty--each UniBit step drill is warranted to be free from defects in material and workmanship for the life of the tool, except for damage caused by abuse, misuse, or alteration.