The Flowmaster® American Thunder® Cat-back exhaust system for the 2020-2026 Chevy Silverado and GMC Sierra 2500HD and 3500HD trucks with the 6.6L gas engine, has a moderate to aggressive sound level inside and outside of the truck, with all of the performance benefits you expect from Flowmaster®. Designed for the Crew Cab, Standard Bed (6.5 ft.) models only, this bolt-on, emissions-legal system features a stainless steel 50 Series HD™ muffler and large dual 3.00-inch 409 stainless steel mandrel-bent tailpipes that can be configured to exit either dual straight out the back, or dual out the sides behind the rear wheels which is best suited for towing applications. The system is finished off with a pair of large 4.00-inch polished 304 stainless steel tips and is covered by our Lifetime Limited Warranty. Designed for an easy fit, this system includes all necessary parts and hardware for installation. Notes: Fits Crew Cab with 6.5' bed length, 159-inch wheelbase only. Will not fit models with 5th wheel tow hitch installed.