Gearbelt Pulley Bore Diameter 1 in For Belt Series SilentSync For Belt Width 105 mm For Use With SilentSync Red Belts Material Steel Number of Teeth 28 Outside Diameter 121.99 mm Pitch 14 mm Pitch Diameter 124.78 mm Bore Type Plain Face Width 107 mm Features Self-Tracking Design For Belt Trade Size R-28S Keyway No Keyway Depth Not Applicable Keyway Width Not Applicable Length through Bore 107 mm Material Fabrication Machined Maximum Operating Temperature 200 Degrees F