Precision Twist Drill Screw Machine Drill, Heavy Duty, Series: R40C, Imperial, 5/16 in Drill - Fraction, 0.3125 in Drill - Decimal Inch, 2-13/16 in Overall Length, 2.5XD Cutting Depth, 2 Flutes, Spiral Flute, 1-5/8 in Flute Length, 5/16 in Shank, Straight Shank, 135 deg Point, Split/Self-Centering Point, Right Hand Cutting Direction, HSS Cutting Edge, HSS, Oxide Treated, Dark Gray, Applicable Materials: Steel, Stainless Steel, Cast Iron, Titanium, Nickel, Copper, Aluminum Magnesium, Synthetic Materials and Hard Materials