AMSOIL Ea Oil Filters have the best efficiency rating in the industry. EaO Filters provide a filtering efficiency in accordance with industry standard ISO 4548-12 of 98.7 percent at 15 microns, while competitive filters containing conventional cellulose medias range from 40 to 80 percent efficiency. Made with premium-grade full synthetic media. Ea Oil Filters feature advanced full synthetic nanofiber technology, making them the highest efficiency filters that are available for the auto/light truck market. AMSOIL EaO Filters are guaranteed for 25,000 miles or one year, whichever comes first, when used in conjunction with AMSOIL Synthetic Motor Oil in gasoline and diesel vehicles in normal service, 15,000 miles in severe service.