The multi-link rear suspension of the C4s were an improvement for this generation Corvette. Replacing the factory rubber bushings with urethane has some advantages but the only real way to maximize the rear grip of your C4 is to use a spherical rod end type suspension. Now we certainly cannot take credit for being the first to put rod ends on a Corvette. BUT, we can take credit for designing a system that has been track tested to improve rear grip and reduce lap times as well as improve grip and handling on the street. We also feel our system is easier to setup and make sure your suspension settings stay where they should over time. All our suspension links are made up of aluminum bodies with a red anodize finish and use American made Aurora Bearing steel bodied, Teflon lined rod ends. The rod ends are the key to the system since they are what frees up the binding of the rear suspension as compared to the stock dog bone style links. Since the rod ends are Teflon lined there is no need for greasing before installation or maintenance once they're installed. Another feature of our kit is the locking mechanism once the links have been set to the desired length. Many other kits out there use jam nuts to hold the rod ends in place. In short, that's the old way to do it. Our kit uses an omega clamp that fits over the end of the aluminum links that are slotted, like a collet. When the screw of the omega clamp is tightened, it pulls the collet tight over the threaded portion of the rod end, holding in place securely without marring the thread or the body. This is done simply with a 1/4" 12-point socket (not included) and does not require getting two large wrenches into tight areas like jam nuts can. This kit comes with everything you need to replace your upper and lower trailing arms on both sides of your C4. The spacers supplied with this kit relocate the trailing arms slightly towards the outside of the Corvette. This increases the clearance between the trailing arms and the shocks, which is especially important if your Corvette has coilovers.