These replacement tension arms are machined from 6061 T6 billet aluminum and have been fully FEA (Finite Element Analysis) tested, and have shown to be more than twice the strength of the stock steel or cast aluminum OE part.  One end features bushings that are 85 durometer providing less deflection and distortion.  The other bushing is a FRB (fiber reinforced bushing), tested to over 60,000 psi.  This combination provides for an extremely strong part with virtually no noise and harmonics.  These tension arms are critical in keeping the rear stable and preventing oscillation.