This PTO oil seal protects the drive system output shaft by retaining lubricant and excluding contaminants. It sits at the rear of the transmission housing where the PTO shaft exits, preventing oil loss from the gearbox and keeping debris from entering the bearing area. A worn seal allows oil to weep along the shaft, which can lead to low lubricant levels and eventual bearing damage. This original AGCO seal is molded to the same lip profile and spring tension as the factory component, so it maintains the correct contact pressure against the shaft without requiring shimming or adapter rings. On installation, inspect the shaft surface for scoring and replace the seal with the lip facing inward toward the oil supply.