Add rigidity and precision to throttle input control to your Subaru with our PERRIN PerformanceTM Sub Frame Lock Out Kit. Lock down the back end and give yourself more controlpower. Kit includes polyurethane bushing inserts and bolt-in frame lockouts to completely lock-up the rear sub-frame, differencial and trailing arms. This elminates all driveline slop and especially the annoying thud from first to second gear changes that are found without this kit. An inexpensive upgrade that nets such dramatic results. Fits Impreza models including WRX and STi.