MILWAUKEE® THUNDERBOLT™ Cobalt drill bits are designed for extreme durability and long life in specialty applications. The THUNDERBOLT™ web features a thicker core than a standard drill bit to provide ultimate strength and protect against side-load breakage. A specially designed parabolic flute form clears chips and debris fast to keep the bit cool. The 135° split point tip delivers a precision start and prevents walking for fast, accurate holes. Effective for drilling on curved surfaces, MILWAUKEE® THUNDERBOLT™ Cobalt bits require less effort to drill through stainless steel, high alloy steel and cast iron, and are highly recommended for use with portable drills.
135° split point for precision start no walking
RED HELIX™ Design for Rapid Chip Removal™
Up to 10X Life vs. Black Oxide
Secure Grip™ - Prevents bit from slipping in chuck
3-Flat Secure-Grip™ helps keep the bit fixed within the the chuck