Our SPL FKS monoball bushings for the rear knuckle replace the stock mushy rubber bushings with Teflon lined FK spherical bearings, eliminating bushing flex and reducing bind/friction. This maintains optimum suspension geometry under load, to improve handling and feedback. Our SPL FKS series bushings feature FK racing bearings with a self lcleaning Teflon liner for long life and maximum performance. Highly precise (machined to 1/1000th inch) CNC machined T6061 aluminum bearing shell provide an accurate fit. Made in the USA. Note: For Twinturbo models. Does not include HICAS balljoint replacement.