Individually tested standard capacity media. Galvanized Steel cell sides. HEPA grade filter with economical particle board sides. 99.99% at 0.3µ. Media is submicron glass fibers formed into a water-resistant, high efficiency high density, wet-laid paper mat. UL rated. Applications include air handlers in medical facilities, pharmaceuticals, clean room manufacturing and indoor gun ranges. Maximum continuous operating temperature 180° F. Furnished with one gasket on the downstream side. Initial resistance (inches W.G.): 1.0.