Pro GUARD7 Media: This filter features Pro GUARD7 Media that consists of 5-Layers of progressively finer mesh oiled cotton gauze and 2-layers of finer porosity synthetic non-woven media for maximum protection in the most extreme environment. The Pro GUARD7filter media has been tested at 99.51 percent filtration efficiency. Massive Washable/Reusable Filter: With 8-1/2" Base x 8-1/2" Top x 11" Height with a 4" flange, this filter is a flexible flange version of the popular Donaldson paper filter (P/N: ECB085011). Rather than throwing the filter away, you can now wash the filter and reuse it over and over again. Rounded Open Pleats: aFe performance air filters use a rounded, evenly spaced pleat design which produces more useable filter surface area for increased flow and greater dust holding capacity. 100% polyurethane construction: To allow multiple cleaning cycles, the top and base are made of 100% pliable polyurethane that does not deteriorate with time or exposure to heat and chemicals. Magnum SHIELD Pre-Filter: Protects your performance air filter from debris, repels water and keeps your air filter clean longer with minimal affect on air flow. aFe Power Universal Clamp-on performance filters have a limited 2-year warranty.