Service replacement part for the FR500S and BOSS302 R1 race car Fits 2005 - 2014 Mustang. Also for use on NASA AI and AIX class S197 Mustangs Allows adjustment to the rear suspension vs the factory non-adjustable bar. 1.125" OD x.095 wall thickness 4130 chrome moly bar Low deflection urethane rod ends and steel sleeves Offset mounts allows bar to clear rear differential cover