Eliminate  wheel hop, increase traction and improve handling   performance with an easy bolt  on installation. UMI Performance’s   adjustable upper controls feature on car  adjustability and are supplied   with spherical Roto-Joints. The Roto-Joint design  is a pivot ball   lined with a greaseable delrin race designed to offer 28 degrees  of   total unrestricted movement, more than adequate for a bind free, low   friction  operation. The Roto-Joint design improves performance over the   factory rubber  and aftermarket polyurethane bushings by allowing the   suspension to articulate  correctly, and provide precision handling. The   installed UMI Roto-Joint allows  rear end free movement when high   handling, auto cross or road race is a concern  while still being a 100%   streetable setup. The installed delrin race, which  lines the spherical   ball, absorbs shock and road noise for a quiet and smooth  operation on   any street or track driven vehicle.
Installation Instructions