Bore Miter Gear Bore Diameter 18 mm Bore Diameter Tolerance H7 Bore Type Finished Face Width 12 mm Finish Black Oxide For Shaft Angle 90 Degrees Gear Shape BK Hub Diameter 40 mm Hub Projection 10 mm Hub Type Hub with Set Screws Includes Set Screw Keyway Yes Keyway Depth 2.8 mm Keyway Width 6 mm Material Carbon Steel Material Grade S45C Maximum Teeth Hardness 60 HRC Metric Module Pitch 2 Minimum Teeth Hardness 50 HRC