Hertel HSS & Cobalt 135 Aircraft Extension Drill Sets

• Grade: Heavy-Duty
• Drill type: split
• Used to drill normal depth holes in hard to reach places
• Supplied in open stand

Tool Material:

HSS

• Provides good wear resistance in mild steels, soft metals (aluminum, copper, brass, bronze) and nonferrous materials.

Cobalt

• Provides better wear resistance in hardness and toughness compared to HSS
• For use in high-tensile alloys, titanium, cast iron, Inconel and high-nickel stainless steel

Coating Advantages:

Black Oxide

• Retains lubricants to aid in wear resistance and chip flow