Mild Tone. T409 Stainless Steel Construction.; Dyno Proven; Your MBRP performance gas exhaust system has undergone countless hours on our in-house Mustang 1100 AWD-SE Chassis Dynamometer, hundreds of miles on road and track and numerous tweaks and modifications to get the most out of your truck. From the vehicle specific muffler design to the fully mandrel bent tubing to minimal bend degree angles, your MBRP performance system gets exhaust out fast. An MBRP performance exhaust system is the starting point to getting the most from cold air intakes, programmers, modules and downloaders.