Vibrant Performance ultra quiet resonators are oval bodied, densely packed with our premium multi-layered sound absorption materials, and manufactured from 304 stainless steel for optimum durability and corrosion resistance. Vibrant Performance ultra quiet resonators feature a larger sound chamber than our standard resonators to further reduce and tune exhaust tones. They are available in inlet / outlet I.D. dimensions ranging from 2.25" to 3".