4 - inch constant - diameter system flows up to 122 Percent better than stock. 5 - inch Chrome or Cerakote Black Tip. The 4 inch Monster exhaust system flows up to 122 percent better than stock and virtually eliminates backpressure. Banks streamlined 4 inch turbine outlet pipe with provision to retain stock catalytic converter, intermediate pipe(s) and tailpipe are formed of stainless, heavy - wall tubing with constant - diameter bends to maximize airflow and lower exhaust gas temps. Banks replaces the factory's restrictive muffler with a polished - stainless Monster muffler featuring a straight - through 4 inch diameter path that flows up to 129 percent better than stock. The Banks - designed expansion chamber dissipates the annoying mid - range exhaust drone that accompanies most straight - through mufflers. Monster muffler utilizes spun ceramic, very - high - temperature packing and delivers an authoritative - but never intrusive - exhaust sound. And the 5 inch polished rolled - edge tip has an adjustable clamp for positioning on tailpipe. Get it in your choice of chrome - over stainless or high temp black (And to help keep it looking good, there's a 12 inch air gap to keep heat from tarnishing the finish). Monster Exhaust System, Single Exit, Chrome or Cerakote Black Round Tip for use with 2003 - 2004 Dodge 5.9L, CCLB Crew Cab Long Bed, with or without Catalytic Converter