Vibrant Performance standard bottle style resonators are round 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 standard bottle style resonators have a sleek design that is optimal for easy installation and work to maximize the reduction of exhaust db levels. They are available in 12 & 18 overall lengths and inlet I.D. diameters ranging from 2.25 to 4.