A unique design that provides an unrivaled combination of power and a quiet exhaust note. The RS-4S features a Polyresonant duplex chamber, a two-staged stepped baffle, and an innovative carbon fiber turn-out end-cap. Pentagonal-shaped sleeve Front muffler cap functions as a polyresonant chamber which helps reduce noise Two-stage stepped baffle Turn-out carbon fiber end-cap Stainless steel tail-pipe