The COBB Tuning Gen1 MAZDASPEED3 Cat-Back is constructed purely from 304 Stainless Steel. The system starts with a stock donut-style flange that mounts to the OEM downpipe or any stock-replacement downpipe, such as the COBB Tuning 3" Downpipe. Next up is a polished resonator section with attractive rolled end-cap, followed by a polished low-restriction straight-through muffler section, also with this attractive rolled end-caps. A thick stainless-steel 2-bolt flange connects to the final section of the exhaust that ends in a tasteful, slash-cut 3.5" double wall tip featuring an etched COBB logo. This COBB Tuning exhaust system conforms to the SAE dictated 95-decibel exhaust noise level limit enforced by California, as well as other states in the US.