This universal joint shaft seal ring is a non-original replacement that prevents fluid leaks at the rotating interface of the PTO shaft assembly. It sits between the shaft and the housing, retaining lubricant inside the joint while excluding contaminants from the bearing surfaces. A worn seal allows grease loss and dirt ingress, which accelerates spline and bearing wear. Corteco manufactures the seal to match the original housing bore and shaft groove dimensions, so the lip contacts the shaft at the correct interference for consistent sealing pressure. On installation, ensure the seal lip faces the lubricant side and that the shaft surface is free of burrs or scoring.