Total 4 new membranes x 50 GPD NFS/ANSI 58 Certified :General Information :The first full tank of permeate should be discarded. Do not use this initial permeate for drinking water or food preparation.Keep elements moist at all times after initial wetting.If operating limits and guidelines given in this bulletin are not strictly followed, the limited warranty will be null and void.To prevent biological growth during prolonged system shutdowns, it is recommended that membrane elements be immersed in a preservative solution.The membrane shows some resistance to short-term attack by chlorine (hypochlorite). Continuous exposure, however, may damage the membrane and should be avoided.Membrane Features :Innovative thin layer composite membrane designAdvanced membrane technologyProvides high rejection stability even with high TDSLess fouling, Less frequency cleaning and More consistent100% dry membrane maximizing shelf lifeLower consumption of chemical and longer lifeCertified to NSF/ANSI 58NSF Certified quality reverse osmosis membrane widely used on household reverse osmosis systems ,aquariums RO systems and applications.Detailed Description :HIGH QUALITY Reverse Osmosis Membrane widely used on household Reverse Osmosis systems ,aquariums RO systems and applications.Fits all membrane sizes 1812 & 2012Membrane 50 GPD Certified to NFS/ANSI 58To remove particles down to 1/10,000 of a micron ( which is 98% of impurities including Organic and inorganic, chemicals).Replace every 2 years. Replacement membrane available in other pack Membrane 50GPD 1 Pack 162005995211 Membrane 50GPD 5 Pack 152691312942 Membrane 50GPD 10 Pack 322792119917 Membrane 50GPD 25 Pack 322792115080 Membrane should be changed every 2 years under domestic conditions. Membrane life varies and depends on the water source quality. –> –> –> –> –> –> –>