aFe 49-03059 ATLAS 3"/3.5" Aluminized Steel Y-Pipe Exhaust System with Catalytic Converter for Ford F-150 V6-3.5L Engine Mitered collectors for increased flow, increases flow and performance for more power No modification necessary direct bolt-on uses factory mounting locations for a hassle-free install 300 cell high-flow catalytic converters free of check engine lights 3 inch to 3-1/2 inch transition for better performance Manufactured and assembled in the USA