... -base, ant-corrosion, high melting point, stable performance,\Water-proof, high strength and can stand the temperature as high as 120°C ... applied for primary, middle, high efficient filters, oil waste treatment, water purification equipments, HEPA filters, etc.Weight per square meters ranges ... .999< 22> 99.5< 110H12120±5high efficient filters high effciency and low resistance air /water filter pp paper