Bilsteins are original equipment on many Porsches and have won, for Porsche, countless races. Bilsteins are the highest quality shocks made and will last the lifetime of your Porsche. Bilstein sport shocks and struts are for the performance minded driver. Bilstein sport units deliver absolute mastery of the road surface. Designed to push a car 's suspension to its performance peak, these super-firm units are well suited for use with special springs, anti-sway bars, and other suspension upgrades. As with other bilstein units, sports are uniquely self-adjusting. Sold each, two needed for the rear of your vehicle.