Milwaukee® Thunderbolt® Black compound distributer length drill bits are designed for extreme sturdiness and long life. The Thunderbolt net options a thicker core than a typical drilling bit to supply final strength and defend against side-load breakage. A specially designed parabolic flute type clears chips and rubble quick to stay the bit cool. The 135° split purpose tip delivers a preciseness begin and prevents walking for quick, correct holes. Effective for drilling on curved surfaces, city Thunderbolt Black compound bits need less effort to drill through metal, wood and PVC, and are extremely suggested to be used with transportable drills.