Precision Twist 502-12 Q X 12 Inch Black High Speed Steel Aircraft Extension Drill 135 Degree Split Point NAS907 Type B 059217

The Precision Twist 500 Series (Including 500-6, 500-12, 501-6, 501-12, 502-6 and 502-12) Extra-Length Aircraft Extension Drill Bit Is A Round Shank Bit Made Of HSS With A Steam Tempering (Also Called Black Oxide) Finish. It Is Suitable For Drilling To A Depth Up To Four Times The Diameter Of The Drill. The Shank Diameter Is The Same As The Drill Size. Best Performance With Drilling Into Hardened, Tempered Alloy Steel, Stainless Steel, And Titanium. These Should Be Less Than 30 On The Rockwell C hardness Scale. While This Drill Series Was Designed For The Aircraft Industry (NAS 907 Type B), They Also Work Well For Drilling Into A Variety Of Materials. The Extra Length And 135-Degree Split Point Drill Geometry Provide Extra Reach And Ensure An Accurate Hole By Reducing Walking When The Hole Is Started. The Finish Retains Lubricants To Aid In Wear Resistance And Chip Flow.