Rubicon Express Super-Flex joints are designed to replace the heim joints used in early suspension designs. The small-size joint is designed to fit directly into the factory front or rear upper control arm mounting points on the XJ/MJ/ZJ/TJ/WJ chassis. They use UHMW side races and a unique threaded adjuster nut which allows easy tightening and rebuilding, if necessary. Rubicon Express ran their JeepSpeed race Cherokee for a complete season on one set of control arms with these Super-Flex joints without a single failure. After removal at the end of the season, they felt as tight as the day they were installed. In contrast, factory rubber bushings need to be replaced at every race!