Milwaukeer Thunderboltr Titanium coated drill bits are designed for extreme durability and up to 3X longer life. The Thunderbolt web features a thicker core than a standard drill bit to provide ultimate strength and protect against side-load breakage. The titanium coating reduces heat build-up and keeps the bit sharp to extend performance. 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 Titanium Coated bits require less effort to drill through wood, metal and PVC, and are highly recommended for use with portable drills. Includes two bits.