The race exhaust systems we carry are made from 16ga mandrel bent steel. Offering both Aluminized and T409 Stainless Steel exhaust systems, we have one of the most diverse products on the market. We have direct fit exhaust kits for your Cummins, Duramax or Powerstroke! With all pre-bent and pre-welded hangers, you never have to guess where a pipe goes. Everything just fits right into place.