09, Minimum Teeth Hardness 50 HRC, Mounting Distance 32.11 mm, Face Width 6 mm, Finish Black Oxide, Gear Shape T9, Hub Diameter 40 mm, Hub Projection 10 mm, Material Carbon Steel, Maximum Teeth Hardness 60 HRC, Metric Module Pitch 2.3 mm, Number of Teeth 100, Outside Diameter 66.Ratchet Gear, Bore Diameter 12 mm, Bore Diameter Tolerance +/- 0.