RO Membrane Housing Use For 50 GPD, 75GPD, 80GPD, & 100GPD RO Membrane Universal Size Membrane Housing 1 pcs + 3 pcs elbow + 1 Taflon TapeStandard Size Reverse Osmosis Membrane Housing Constructed of High Quality PolypropyleneMost trusted in the residential reverse osmosis membrane for performance and qualityThe ribbed cap incorporates acme square threads and O-ring to ensure a leak-proof seal.