This Teflon ring sits inside the clutch basket and acts as a sealing and guiding element for the clutch hub within the gearbox. It maintains the correct axial clearance between the rotating and stationary parts of the clutch pack. A worn or compressed ring allows excessive hub movement, which can cause clutch drag, gear engagement difficulty, and premature wear on the synchronizers. The original AGCO ring is molded to the same thickness and diameter as the original production part, so the clutch stack height and preload are preserved without shimming. On reassembly, verify the ring is fully seated in its groove before installing the clutch basket.