Bordo Long Series HSS Black Drill Bit (2500) - Imperial

• ANSI B94-11.
• 118° chisel point with 30° helix.
• Chisel point is suitable for general purpose drilling.
• Black Finish Twist Drills (also called blue finish) achieve their distinctive colour by steam tempering, a thermal process resulting in a porous tool coating.
• This surface helps to keep lubricant on the tool, particularly important on the cutting edges, thus reducing friction and cold welding. The result is increased tool life.
• Black finish tools are generally recommended for ferrous applications where the oxide layer aids chip flow and heat dissipation.