Sway bar kit, Revo (front and rear) (includes thick and thin sway bars and adjustable linkage) (requires part #5411 to install rear bumper) The Traxxas Revo sway bar kit is a must have for Revo racers everywhere. The kit was created, developed, and extensively field tested by Traxxas driver and reigning monster truck national champion Tim Roberts. The sway bar kit fits Revo, Revo 3.3 and E-Revo and it includes front and rear linkages, mounts, thick and thin sway bars, hardware, a tuning guide, and comprehensive installation instructions.*Can not be used with stock rear bumper mount setup. Must be used with rear wing mount #5411. Traxxas offers a wide variety of spring rates for the GTR shocks to precisely compensate for lighter or heavier truck configurations. The springs use high-quality spring steel with durable powder-coated finishes. Spring rate is indicated by colored dots on the end of the spring.