When your truck rolls out of the factory, it is likely already sporting a factory-designed exhaust system. These are about 5" in diameter and extend up from the muffler to serve their purpose of releasing exhausted fuel fumes and that purpose only.
We consider that a major wasted opportunity for visual bang. As our customers know, a lot of owner-operators out there prefer custom chrome exhaust at least 6" wide. For the more daring trucker, the options only get bigger from there, peaking at a loud and proud 10" pipe meant for catching as many eyes as possible on the road and at truck shows.