Irwin Unibit Self-Starting Step Drill #20

Drills 9/16 to 1 holes in 1/16 increments. Has 8 steps on bit. Single flute cutting edge for greater control through steps. Three flatted shank 1/2 prevents slipping in drill chuck. Speedpoint tip penetrates faster and prevents walking. Ideal for drilling holes into thin materials such as stainless steel, copper, brass, aluminum, plastic and laminates.