Irwin Unibit Step Drill Bit, 10231

Single concave flute design creates perfectly round holes in thin materials including steel, brass, copper, and aluminum. Constructed of industrial grade, high speed molybdenum steel. SpeedPoint tip for fast starts. No. 10231: Minimum Size: 1/8 In., Maximum Size: 1/2 In., Step Range: 1/32 In., Number of Holes: 13 Sizes, Shank: 1/4 In. Hex, Material: High Speed Steel, Pkg Qty: 1, Package Type: Clamshell No. 10232: Minimum Size: 3/16 In., Maximum Size: 1/2 In., Step Range: 1/16 In., Number of Holes: 6 Sizes, Shank: 1/4 In. Hex, Material: High Speed Steel, Pkg Qty: 1, Package Type: Clamshell No. 10233: Minimum Size: 1/4 In., Maximum Size: 3/4 In., Step Range: 1/16 In., Number of Holes: 9 Sizes, Shank: 3/8 In. Hex, Material: High Speed Steel, Pkg Qty: 1, Package Type: Clamshell No. 10234: Minimum Size: 3/16 In., Maximum Size: 7/8 In., Step Range: 1/16 In., Number of Holes: 12 Sizes, Shank: 3/8 In. Hex, Material: High Speed Steel, Pkg Qty: 1, Package Type: Clamshell No. 10239: Minimum Size: 7/8 In., Maximum Size: 1-1/8 In., Step Range: 1/4 In., Number of Holes: 2 Sizes, Shank: 7/16 In. Hex, Material: High Speed Steel, Pkg Qty: 1, Package Type: Clamshell