Drill America #4 Cobalt Heavy Duty Drill Bit (Pack of 12), D/ACO Series

Drill America D/ACO series premium quality heavy duty jobber length drill bit. Manufactured to National Aerospace standard 907. Made of heat resistant cobalt steel, it displays higher red hardness which permits speeds upto 30 percent greater than High-Speed Steel drills and is especially effective in drilling tough, high tensile strength materials like PH stainless steel, inconel and titanium.

• Cobalt steel tools are similar to high-speed steel, but with more cobalt for improved performance when cutting harder metals such as stainless steel or nickel alloys
• Gold oxide is a thinner oxide surface treatment than black oxide typically used to identify cobalt steel tools; performance is similar to uncoated tools
• Round shanks allow use with a wide variety of toolholding systems
• When run in a counterclockwise direction (right-hand cut) spiral fluted tools evacuate chips up and out of the cut to reduce clogging
• Manufactured to National Aerospace standard 907