UMI Performance 91-96 Impala SS Adjustable Extended Length Upper Control Arms- Poly EndsUMI Performance extended length upper control arms are designed to properly center the rear wheels in the vehicles wheel well on the Impala SS. These control arms are extended 5 8 but also feature additional adjustment to perfectly center the rear end. The adjustment allows the user to lengthen or shorten the control arms an additional 1 2 beyond the already extended 5 8 of an inch, all adjustments are made while the control arm stays attached to the