Selling my 2020 GMC AT4 Carbon Pro factory performance cat back exhaust system muffler. It is a flow thru design. This thing is throaty, loud and sounds tough. It is too loud for me and family. The inlet and outlet pipes are centered and are 3.5 in diameter. Exhaust clamps are with it. The cat back system from GMC is nearly $2000. Open for best offers. Thank you.