Every Vibrant Ultra Quiet Resonator is constructed of polished, 304 Stainless Steel for superior durability and show quality looks. Vibrant resonators feature a True Straight Through perforated core, surrounded by premium multi-layer sound absorption materials to dampen noise levels without restricting exhaust flow. The Ultra Quiet Resonators feature a larger sound chamber, which provides better sound dampening than the standard bottle resonator, and eliminates the rifling noise common with 6 cylinder and 8 cylinder engines equipped with straight through performance exhaust systems.