Thermoplastic Grade 1 Type 1 PVC, Corzan CPVC, pressure relief valve, 3" NPT threads, is to be 90º angle pattern featuring fabric reinforced [EPDM or Viton] rolling diaphragm. The valve is to have a solid, machined and polished PVC shaft with PTFE thrust washer; and stainless steel external fasteners. Manufacturer shall factory set the pressure relief valve at [between 5 and 100] PSI. All units are to be 100% individually tested at the factory. As manufactured by Plast-O-Matic Valves, Inc., Cedar Grove, NJ.
ADD: "With tamper-proof option" after pressure setting, if required.