Manufactured to Aerospace Standard 907.. 1/2"x12" HSS Aircraft Extension Drill Bit, Overall Length: 12" Sizes smaller than 1/16 and #52 have the 118 degree standard point. They have a black oxide surface treatment that is abrasion resistant, reduces chip welding and improves chip flow.
The 135 degree split point is self-centering and reduces thrust.. 5/64"x12" HSS Aircraft Extension Drill Bit, Flute Length: 1" Sizes smaller than 1/16 and #52 have the 118 degree standard point.