Fits 2005-2013 Mustang GT and V6 and 2007-2013 Shelby GT500 Standard equipment on 2007-2013 Shelby GT500, 2013 Mustang GT with Track Pack, and 2011-2013 Mustang GT with manual transmission Ford Racing part number M-5538-A Increases bushing durometer and stiffness for higher horsepower applications Includes hardware Note:Some factory fasteners are one-time use. Reference service manuals for re-use & torque specification.