CTD Metric Magnum Super Premium 4mm Drill Bit (2 Pack)
CTD Metric Magnum Super Premium 4mm Drill Bit Part #49270Length = 3 1/4"Flute Length = 2 1/8"Metric Jobber Length Drill Bit Magnum Super Premium        Special Hi-Molybdenum tool steel.        135 split point for fast penetration and accurate starting without center punch.        Precision ground: point, flutes, body, clearance, and drill diameter for the ultimate in accuracy and performance.        Body and clearance are gold surface treated for maximum lubricity.        Heat treated at 2185 F and then nitro-carburize finished at 950 F to be measurably harder than high speed steel.        Nitro-carburized steel withstands substantially higher drilling temperatures while maintaining sharpness.        Especially designed for hand held drills.        Recommended for use in work hardening grades of stainless steel and other hard metal drilling applications.