Flowmaster's® FlowFX Cat-Back exhaust system for the 2020-2026 GM 2500HD and 3500HD trucks with the 6.6L gas engines gives you a great way to help you customize your GM truck to your personality. This performance exhaust system fits both 2/4 Wheel drive models and is manufactured from 409 stainless steel for years of trouble-free service and performance. Features include a 3.50-inch inlet pipe leading into a 409 stainless steel Flow FX series "straight-through" muffler for great sound and maximum performance and no drone. The muffler then connects to the factory tailpipe for a simple and effective performance upgrade. Max dyno gains of 11 hp and 10 lb-ft at the rear wheels. This results in better acceleration and towing performance. The system uses all the factory hanger locations and connections for an easy installation that you can do at home. Kits include installation instructions and all necessary hardware. Backed by Flowmaster's Lifetime Limited Warranty.