Our steel tubing is laser cut and CNC mandrel bent to create frame rails made to tighter tolerances than Jeep could pull off back in the day. TDK frame rails are made from 2x4 3/16" A500 steel tubing, which is stronger than the steel used in OEM frame rails. If you're building a CJ, don't spend hours cleaning up an old frame only to have it rust again. TDK frame rails are the way to go! There are many features included and options available, including custom bending. Click below to learn what is possible.