This Problem Solver deals with these problems:* Stabilized piston will not flip in the servo bore.* Moves lip seal up and out of worn area in bore. (case saver) * Constructed of steal for strength Superior K029 727,518 Low & Reverse Steel Super Servo This newly designed piston is much wider and uses a teflon support ring along with lip seal to create a completely stable piston. This piston will not flip in the bore.2. The lip seal has been moved up to enable it to work in a less worn portion of the bore. This can prove as a real case saver.3. This servo is available for 727 thru A518