Worm Wheel Bore Diameter 8 mm Bore Diameter Tolerance +/- 0.2 mm Bore Type Plain Face Width 11 mm Gear Shape H1 Hub Diameter 30 mm Hub Projection 9 mm Material Bronze Metric Module Pitch 1.25 Number of Starts 1 Number of Teeth 40 Outside Diameter 53.8 mm Overall Length 20 mm