Molded-composite left right back upright features included 1° of outboard toe-in to improve the rotation from the car in corners preventing suspension system system geometry alterations in serious crashes. Features two roll center jobs ahead about the back upright. Accommodates little but robust 5x10 ball-bearings for minimized unsprung fat.
rough rigidity (labeled H) especially optimized for foam-tire race.
Use with matching right-side right back upright 303353. Might be also perfect for plastic tires.