Exhaust Adapters will help your 2017-2019 Chevy/GMC 6.6L L5P Duramax add the larger tip onto your stock exhaust. Y-pipes and exhaust reducers typically start at 3.5" and go all the way to 7" in diameter so that they can be used in a wide variety of applications. Adapters are available in a wide range of materials like Aluminized and stainless-steel to properly match your existing exhaust application. Get industry leading manufacturers such as Silverline, Magnaflow, and MBRP.