Thunderbolt 3/16 3-1/2 OAL Cobalt Drill Bit,

Milwaukee Thunderbolt 3/16 3-1/2 OAL Cobalt Drill Bit, 48-89-2309. 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, which provides ultimate strength and protects against side-load breakage. A specially designed parabolic flute form clears chips and debris fast to keep the bit cool. A precision start, 135 Split Point tip starts on contact to keep the bit from walking for fast accurate holes. Excellent for drilling on curved surfaces, requires less effort to drill and is highly recommended for use with portable drills. Thunderbolt Web, Provides Longer Life and Faster Driller Times. Parabolic Flute, Clears Chips Faster. 135° degree Split Point, Precision Start No Walking. Specialty Bit for Cast Iron and Stainless Steel.