This part fits the cast aluminium arm only as fitted to the RS models. It features two steel outer shells to dissipate energy and increase the stiffness of the bush. Additional caster offset of 0.6 provided by the offset stainless steel sleeve. For a non-adjustable version of this bush please use PFF60-702. In our Road Series purple material, stiffness is increased by over 100% when compared to the original rubber bush.