MBRP 15-16 Chevy/GMC 6.6L Duramax 3in Down Pipe (For 3 Bolt Flange Style Connection)Replace that restrictive factory downpipe with a MBRP direct replacement downpipe for more flow, fuel economy, and better performance. Removal of OEM catalytic converters may be a violation of emissions laws in your jurisdiction. Ensure that the intended use of this product is permitted. Not for sale or use in the state of California. This Part Fits: Year Make Model Submodel 2015 2016 Chevrolet Express 2500 Base 2015 2016 Chevrolet Express 3500 Base