The rear Extreme system takes it to the next level allowing you to layout on a 29" tall tire by utilizing a bolt-in c-notch for added axle clearance. The latest version of our Lincoln Extreme Rear Air System has an improved design with additional adjustment to ease installation and ensure a proper fit. The system features a 100% bolt-in triangulated 4-link system that rides great and installs easy. The Extreme system includes link bars, subframe structure, axle brackets, KYB shocks and c-notch brackets as well as all required hardware.