The MILWAUKEE THUNDERBOLT 21PC Black Oxide Drill Bit Set offers heavy-duty performance on the jobsite. Black Oxide coating reduces heat build-up and provides corrosion resistance. The thicker core provides ultimate strength and protects against side-load breakage while 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. MILWAUKEE THUNDERBOLT Black Oxide Coated bits are ideal for various drilling applications in wood, plastics, and metals. The set is organized in a customizable accessory case designed for use in PACKOUT.