Milwaukee® Thunderbolt® black compound wholesaler length drill bits are designed for extreme sturdiness and long life. The thunderbolt net options a thicker core than a regular bit to supply final strength and shield against side-load breakage. A specially designed parabolic flute type clears chips quick, whereas the 3-flat Secure-Grip™ shank holds the bit firmly within the drill chuck. The 135° split purpose tip delivers a exactness begin and prevents walking for quick, correct holes. Effective for drilling on sickle-shaped surfaces, city thunderbolt black compound bits need less effort to drill through metal, wood and PVC, and are extremely counseled to be used with moveable drills.