Norseman ny Viking Drill and Tool (6 Pack), 7/32"/6" Type 211 135 Degree Split Point HSS Balk Aircraft Type B Drill Bit.High Speed Steel 6-inch 135-Degree Split Point Solid Construction Black Oxide NAS 907B. 135-Degree split point for accurate centering and fast penetration. High speed steel provides good wear resistance, can be used in general purpose applications for ferrous and nonferrous materials. Black oxide prevents chip building, galling and welding. Commonly used for low carbon, stainless and ferrous metals. NAS 907B Aircraft Length 6-inch OAL (68560)