Drill America #31 X 12" Cobalt Aircraft Extension Drill Bit

Drill America Cobalt Aircraft Extension Drills 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 ...Drill America Cobalt Aircraft Extension Drills 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.

Drill America Aircraft Extension Drills are manufactured to National Aerospace Standard 907. The 135° split point is self-centering and reduces thrust. Sizes smaller than 1/16 have the 118° standard point.

Drill America Aircraft Extension Drills are available in 6 in. and 12 in. overall lengths when extra reach is required.