The Airaid Direct Fit Replacement Air Filters are tested to SAE standards and can capture 99.997 percent of particles of 10 microns and larger size. The combination of 304 stainless steel and five layer media enhances the durability of these filters. Durable media and premium urethane body facilitates superior filtration. These filters contain multiple cotton gauze layers, a SynthaFlow layer that is the final layer of defense assuring the cleanest air possible from any washable filter, and durable epoxy-coated wire mesh specially designed to provide optimum balance between maximum air flow and peak filtration.