12 pieces 9/32 In. x 4-1/4 In. Cobalt Drill Bit

Model: CO4145
Actual Product may vary from the item shown
Bosch cobalt drill bits are specially designed for drilling in hard steel. Thick web helix delivers fast material removal combined with increased durability for maximum efficiency and performance. Each bit is manufactured to exacting specifications and features a split point that starts on contact with no walking or skating, eliminating the need for a center punch.
Benefits: CO4145 12 pieces 9/32 In. x 4-1/4 In. Cobalt Drill Bit
  • Withstands high-temperature applications for extended periods of time (up to 1,100°F)
  • Rigid, thick web design adds stability to bit in tough applications
  • Surface hardened to penetrate tough abrasive materials
  • Available in jobber length, full shank
  • Best used for drilling into light-gauge metal, high-carbon steel, aluminum and ally steel, cast iron, stainless steel and titanium
Specifications: CO4145 12 pieces 9/32 In. x 4-1/4 In. Cobalt Drill Bit
Overall Length4-1/4"
Quantity6 (bulk)
Shank Diameter9/32"
*Note1/64” – 7/64”: 118° point; 1/8” and larger; 135° point; three flat shank 3/16” and larger
View More Sizes
Item #ReviewsDiameterOverall LengthQuantityShank Diameter 
CO215313/32"5-1/4"1 (carded)13/32"
CO215225/64"5-1/8"1 (carded)25/64"
CO21513/8"5"1 (carded)3/8"
CO215427/64"5-3/8"1 (carded)27/64"
CO215715/32"5-3/4"1 (carded)15/32"
CO215629/64"5-5/8"1 (carded)29/64"
CO21557/16"5-1/2"1 (carded)7/16"
CO215023/64"4-7/8"1 (carded)23/64"
CO21459/32"4-1/4"1 (carded)9/32"
CO214417/64"4-1/8"1 (carded)17/64"
CO21431/4"4"1 (carded)1/4"
CO214619/64"4-3/8"1 (carded)19/64"
CO214911/32"4-3/4"1 (carded)11/32"
CO214821/64"4-5/8"1 (carded)21/64"
CO21475/16"4-1/2"1 (carded)5/16"
CO213811/64"3-1/4"1 (carded)11/64"
CO21375/32"3-1/8"1 (carded)5/32"
CO21369/64"2-7/8"1 (carded)9/64"
CO21393/16"3-1/2"1 (carded)3/16"
CO214215/64"3-7/8"1 (carded)15/64"
CO21417/32"3-3/4"1 (carded)7/32"
CO214013/64"3-5/8"1 (carded)13/64"
CO21351/8"2-3/4"1 (carded)1/8"
CO41281/64"3/4"12 (bulk)1/64"
CO21591/2"6"1 (carded)1/2"
CO215831/64"5-7/8"1 (carded)31/64"
CO21311/16"1-7/8"1 (carded)1/16"
CO21347/64"2-5/8"1 (carded)7/64"
CO21333/32"2-1/4"1 (carded)3/32"
CO21325/64"2"1 (carded)5/64"
CO41431/4"4"12 (bulk)1/4"
CO41557/16"5-1/2"6 (bulk)7/16"
CO415427/64"5-3/8"6 (bulk)27/64"
CO415313/32"5-1/4"6 (bulk)13/32"
CO415629/64"5-5/8"6 (bulk)29/64"
CO41591/2"6"6 (bulk)1/2"
CO415831/64"5-7/8"6 (bulk)31/64"
CO415715/32"5-3/4"6 (bulk)15/32"
CO415225/64"5-1/8"6 (bulk)25/64"
CO41475/16"4-1/2"6 (bulk)5/16"
CO414619/64"4-3/8"6 (bulk)19/64"
CO414821/64"4-5/8"6 (bulk)21/64"
CO41513/8"5"6 (bulk)3/8"
CO415023/64"4-7/8"6 (bulk)23/64"
CO414911/32"4-3/4"6 (bulk)11/32"
CO413811/64"3-1/4"12 (bulk)11/64"
CO41375/32"3-1/8"12 (bulk)5/32"
CO41369/64"2-7/8"12 (bulk)9/64"
CO41393/16"3-1/2"12 (bulk)3/16"
CO414215/64"3-7/8"12 (bulk)15/64"
CO41417/32"3-3/4"12 (bulk)7/32"
CO414013/64"3-5/8"12 (bulk)13/64"
CO41351/8"2-3/4"12 (bulk)1/8"
CO41303/64"1-3/4"12 (bulk)3/64"
CO41291/32"1-3/8"12 (bulk)1/32"
CO414417/64"4-1/8"6 (bulk)17/64"
CO41311/16"1-7/8"12 (bulk)1/16"
CO41347/64"2-5/8"12 (bulk)7/64"
CO41333/32"2-1/4"12 (bulk)3/32"
CO41325/64"2"12 (bulk)5/64"

Reviews: CO4145 12 pieces 9/32 In. x 4-1/4 In. Cobalt Drill Bit

Support: CO4145 12 pieces 9/32 In. x 4-1/4 In. Cobalt Drill Bit
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Additional Information: Cobalt Drill Bits
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Cobalt Drill Bits


Cobalt Drill Bits