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Bosch 21 pc. Drill Bit Set, Cobalt M42

Bosch CO21B
SKU BPT-CO21B
Bosch's 21 piece drill bit set is engineered with M42 alloy containing 8% cobalt delivering 10x life vs. standard bits. Thick web-helix design delivers fast material removal and increased stability. Explore more drill bits at HomElectrical.com today!
Bosch 21 pc. Drill Bit Set, Cobalt M42

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Bosch CO21B Description

  • 21 Piece Set.
  • Includes:
    • (2) 1/16-in.
    • (2) 5/64-in.
    • (1) 3/32-in.
    • (1) 7/64-in.
    • (2) 1/8-in.
    • (1) 9/64-in.
    • (1) 5/32-in.
    • (1) 11/64-in.
    • (2) 3/16-in.
    • (1) 13/64-in.
    • (1) 7/32-in.
    • (1) 15/64-in.
    • (2) 1/4-in.
    • (1) 5/16-in.
    • (1) 3/8-in.
    • (1) 1/2-in.
  • Cobalt M42 drill bit - provides upgraded M42 cobalt jobber-length bits designed for durability.
  • Enhanced M42 alloy material - contains 8% cobalt alloy that delivers 10X life vs. standard bits.
  • High-heat resistant bits - withstand high-temperature applications for extended periods of time.
  • Hardened exterior - made to provide durability in stainless steel, cast iron, titanium, light-gauge metal and aluminum.
  • Thick web-helix design - provides additional stability in tough applications.
  • Surface-hardened tip - penetrates tough abrasive materials.
  • Split points on bits 1/8-in and larger - allow for easy starts with no skating, eliminating the need for a center punch.
  • Three-flat shank on bits 3/16-in and larger - deliver better bit grip.
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$155.09Each

Ships between 08/03/2026 - 08/07/2026

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Product Specifications

Part NumberCO21B
Weight1.19-lb
UPC000346594607

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Manufacturer Description

21PC COBALT M42 DRILL BIT SET
Prop65
Important PROP 65 InformationWarning: This product can expose you to chemicals, which are known to the State of California to cause cancer, birth defects, or other reproductive harm. For more information, go to www.p65warnings.ca.gov. to CA residents.

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