Precision-woven, 304 stainless steel, outer-screen construction offers triple-layer protection and increased air flow over stock filter, which may require re-jetting or re-mapping. The "triple-layer protection" contains two epoxy-coated layers of strong steel mesh and one layer of non-woven material. It will last the lifetime of your vehicle with proper care. Corrosion-resistant. Washable and reusable, environmentally friendly.