Molded-composite back upright features fundamental 0° of outboard toe to enhance traction and prevent suspension system geometry changes in serious crashes. Features two roll center jobs over straight back upright. Accommodates tiny but robust 5x10 ball-bearings for minimized unsprung fat.
moderate rigidity (labeled M) especially optimized for rubber-tire race.
Use on both remaining and right edges linked to car. Are helpful for foam tires.