Gearbelt Pulley Bore Diameter 1/2 in For Belt Series SilentSync For Belt Width 64 mm For Use With SilentSync Purple Belts Material Steel Number of Teeth 20 Outside Diameter 49.56 mm Pitch 8 mm Pitch Diameter 50.93 mm Bore Type Plain Face Width 65 mm Features Self-Tracking Design For Belt Trade Size P-20S Keyway No Keyway Depth Not Applicable Keyway Width Not Applicable Length through Bore 64 mm Material Fabrication Machined Maximum Operating Temperature 200 Degrees F