[Features] This gear is commonly used for changing the direction of a rotating shaft. [Features] Material: EN 1.1191 Equiv. (JIS G 4051) Tooth profile, accuracy: Solid teeth, class JISN8 (formerly class JIS4) Pressure angle: 20° Helix angle: 45°. Surface treatment: Black oxide coating. Surface finish of the tooth: Cutting. Bore diameter tolerance: JIS H7 class.