Hunter Industries PGV Valve, Screw-Top, 1"Valve with Femal Thread Inlet and 1" FemaleTthread Outlet with Flow Control Adjustment. The PGV Valve has an external and internal manual bleed allows for quick and easy activation at the valve. The double-beaded diaphragm seal design ensures leak-free performance and the captive bonnet screws eliminate the possibility of lost parts during disassembly. Get maximum performance with the PGV Valve! Perfect for handling the demands of residential systems, this high-quality option provides convenience, reliability, and easy servicing. Choose from an array of configurations to meet your specific project needs. All models feature durable, high-grade, corrosive-resistant, and UV-resistant PVC construction along with a rugged, double-beaded and leak-proof diaphragm to prevent stress failure.