4WD does not play around when it comes to frames. 4WD carries only Blue Torch and Throttle Down Kustoms frame rails because those are the only two quality enough to offer to 4WD's discerning Jeep drivers. The Throttle Down Kustoms frame rail was designed specifically for 4WD and is carried exclusively by us. The design is based on 4WD's own frame research. The Blue Torch frame rail offers the choice of bolting it onto your Jeep or welding it onto your Jeep. It is made of bare steel which can be coated or painted to fit your Jeep's style.