MBRP Sport Series mufflers offer a mild exhaust note over their Utility Series systems, taking full advantage of the reliability and dependability of a chambered design, while increasing flow. MBRP Sport mufflers (SP) offer a mild exhaust note over our utility system, while increasing flow and power, 4.25" muffler. Lighter than stock and constructed of 304 stainless and ceramic coated materials. No clutching required.