Milwaukee® Jobber Length Drill Bit, Series: Thunderbolt® Secure-Grip™, Imperial, 21/64 in Drill Size - Fraction, 0.3281 in Drill Size - Decimal Inch, 4-5/8 in Overall Length, 3-5/16 in Cutting Depth, Parabolic Flute, 3-5/16 in Flute Length, 3/8 in Shank, 3-Flat Shank, 135 deg Point, Split Point, Steel Cutting Edge, Steel, Titanium Coated, Applicable Materials: Ferrous Metal, Non-Ferrous Metal, Plastic and Wood Longer life - titanium coating reduces heat build-up for upto 3X longer lifeExtreme durability - thicker web provides greater strengthFast, accurate drilling - 135 deg split point tip starts on contact to prevent walking, while the parabolic flute clears chips fastReduced slipping: 3-flat Secure-Grip shank holds the bit firmly in the drill chuckVersatile - Reduced shank diameter for use in 3/8 in chucksCorrosion-resistant - titanium coating keeps the bit sharp and provides added protection from heat build-up