Bottom Torque Mount Bush Insert For Ford Focus MK2 RS/STWhy SuperPro? We innovate The base material used by SuperPro is a polyurethane elastomer; a class of Thermosetting synthetic polymer that involves the reaction of various types of isocyanate resins with curing agents, to give an extremely durable material with the best features of rubber and plastic. Since the introduction of polyurethane into the aftermarket suspension industry in the early 80s many have tried but few have succeeded in manufacturing