Dynomax DMX17282 Ultra-Flow Muffler 100% Stainless Steel construction for maximum life. Polished 304 shell for mirror-like apearance. Ultra Flo technology features straight-through design for maximum flow and power. CRF (Continuous Roving Fiberglass) technology delivers a deep, powerful, true performance sound. Ultra Flo systems follow the O.E. routing and attach directly to O.E. mounting locations