Light commercial and residential RO storage composite pressure vessel. High strength precision molded internal liner reinforced with continuous strand fibreglass and sealed with high grade epoxy resin. Polypropylene lower water chamber with 100% butyl diaphragm. Lightweight, non-corrosive construction for maximum life and maximum flexibility. Tank Volume Height Diameter Connection Size Weight Drawdown 40 Gallon 36.9" 21.4" 1.25" NPT 38 lbs 24.7 Gallons Materials of Construction Shell: Chemically coupled polypropylene. Connection: Male socket, Rigid PVC. Water Chamber: 100% butyl diaphragm with polypropylene lower chamber. Ratings & Certifications Max. Working Pressure 125 PSI Max. Working Temperature 120 F WQA-NSF/ANSI 61 WQA-NSF/ANSI 372