Blade is made of heat treated high speed steel with CBN polishing; Delivers a deep, sharp cutting blade; Works better with relatively slow cutting speed (10-20 m/min); Material of Blades: Steel, casting, non-ferrous metal and light metals; Number of blades: 3.8 mm Effective blade diameter: 1.0 inches (25 mm); Total length: 2.6 inches (67 mm); Shank diameter: 0 mm); Surface treatment: Titanium coating. Tip angle: 90; 3 blades; Tip angle: 90°; For drilling machines; High speed steel (HSS)