4 inch stainless constant-diameter pipes and straight-thru muffler nearly doubles flow. Lower exhaust temps. Virtually no backpressure. Rich, throaty sound. Monster exhaust system flows up to 91.5% better than stock and virtually eliminates backpressure. The streamlined 4 inch intermediate pipe(s) and tailpipe are formed of stainless, heavy-wall tubing with constant-diameter bends to maximize flow and lower exhaust gas temps. Banks replaces the factory's restrictive muffler with a polished-stainless steel Monster muffler, featuring a straight-through 4 inch diameter flow-path with a Banks-designed expansion chamber which dissipates the annoying mid-range exhaust drone that's so prominent in competitors' straight-through mufflers. The muffler utilizes spun ceramic, very-high-temperature packing, more than doubles the stock flow and delivers an authoritative - but never intrusive - exhaust sound. Includes a 3-1/2 inch turbine outlet pipe (T.O.P.).* A huge 5 inch stainless steel tailpipe tip in your choice of polished chrome-over stainless or high-temp black sports a rolled edge. And to help keep it looking good, there's a 1/2 inch air gap to keep heat from tarnishing the finish. An adjustable clamp lets you position it on the tailpipe just right. *Banks turbine outlet pipe not required for '06 Power Stroke with manual transmission.