This 4.5" System for the 2011-2016 Super Duty is one the best riding suspension systems ICON has ever developed. This system has been engineered using the highest quality materials and components. The dual rate front coil springs combined with our ICON 2.5 Aluminum Series CDCV shocks give these trucks the performance they so desperately need. This system comes complete with front coils shocks radius arm drop down brackets rear blocks and U-bolts and our patented adjustable track bar giving the front end of these trucks perfect track alignment. The Stage 4 system also includes shocks that feature the ICON Compression Damping Control Valve (CDCV) and our 4-Link kit for the ultimate in shock technology and suspension technology.