Aluminum reduced suspension system owner the FRONT concerning the back suspension redesigned combined with fresh HS bulkheads for an expanded choice of set-up modifications. The rear suspension holders allow installation in upright or inverted orientations, ultimately causing additional roll center places the inner hinge pins. The downward orientation associated with suspension system owner is utilized primarily for Dirt songs. The upward orientation of the suspension holder can be used mainly for Carpet songs. The suspension system holders enable use of both long or standard suspension system supply designs. Machined from premium Swiss 7075 T6 aluminum and black coated. Fits XB4'21