All thermoplastic valves shall be plug gate style constructed from PVC type I, ASTM D 1784 cell classification 12454 or CPVC type IV, ASTM D 1784 cell classification 23447, with polypropylene bonnets and high impact polypropylene hand wheel. All valves shall have non-rising stem and plug-style polyethylene gate with strain-equalizing thread. All valve components shall be replaceable. All 1/2 in - 2 in valves shall be pressure rated to 235 psi and all flanged valves 1/2 in - 8 in to 150 psi for water at 73 deg F, as manufactured by Spears® manufacturing company.