This Genuine CSM 80 GPD Original RO Membrane For RO / UV System KENT Water Filter for All domestic RO - CSM 80 GPD can be used till 1500 TDS. The CSM TFC Reverse Osmosis Membranes are made of the good quality spiral-wound Polyamide and offer outstanding pollutant rejection at water pressures up to 125 psi. You can use till 3 years intervals or sooner only if TDS levels increase beyond normal levels. This deliberate matching of design increases the efficiency and effectiveness of the contaminant rejection of the membrane along with optimizing the amount of rejected water necessary to clean the membrane during normal everyday use. Standard size fits most 4 and 5 stage residential RO systems with flow restrictions rated at 80 gallons per day. This membrane is tested and certified under NSF / ANSI Standard 58 for material requirement.