With five layers of progressively finer mesh cotton gauze media between 100% polyurethane top and base, this high flow "oiled" performance filter provide maximum performance with the highest cumulative filtration efficiency for severe duty environments. Outside expanded metal protects as well as enhances the look of the filter. Washable and reusable for multiple cleanings, the tall open evenly spaced pleats provide excellent dust holding capacity for longer service cycle between cleanings. Pliable polyurethane with integrated bumps insures tight, no leak seal over the life of the filter.