With five layers of progressively finer mesh cotton gauze media and two layers of synthetic media and a 100% polyurethane top and base, this high flow "oiled" performance filter provide maximum protection with highest cumulative filtration efficiency for severe duty environments. Washable and reusable for multiple cleanings, the tall open evenly spaced pleats provide excellent dust holding capacity for longer service cycle between cleanings. Inverted top design offers additional dust holding capacity for longer service cycle. Pliable polyurethane flange with integrated bumps insures tight, no leak seal over the life of the filter. The air filter is wrapped in reinforced metal providing maximum strength to prevent filter collapse.