IRWIN Unibit Hole-Enlarging Step Drill #10221
10 Hole Sizes, 13/16 to 1-3/8″ Hole Dia.

Features:

• UNIBIT Step Drills have an exclusive single radial concave flute.
• This design allows the drilling of perfectly round holes in thin materials quickly and with less effort.
• Each bit is constructed of industrial grade high speed molybdenum steel, and is heat treated to a hardness of between 61 – 63 RC. This assures maximum strength and long life.
• Shank size: 1/2″
• Step thickness: 1/8″

Benefits:

• High Speed Steel (HSS) provides good wear resistance and can be used in general purpose applications on both ferrous and non-ferrous materials.
• Bright provides a smooth, polished finish on the tool. It increases chip flow in softer materials such as aluminum, wood and plastic.
• Round shanks with flats are ground flat on three sides for increased chuck grip, reducing slippage and help centering the drill in the chuck. They are used with portable drills and drill presses on ferrous and non-ferrous materials.

Specifications:

See all IRWIN Unibit Hole-Enlarging Step Drills