This 2?” Sch 80 PVC True Union Diaphragm Valve, VITON, (FNPT x FNPT) is a true union diaphragm valve restrics flow through it as the handel is turned. The clear section on top allows you to see the valve position. a male adaptor, threaded pipe or pipe nipple connects to this part. Sch 80 PVC is robust and durable, perfect for commercial and industrial applications. VITON seals provide increased temperature resistance than EPDM seals and recommended for exposure to oils, gasoline and aggressive chemicals. Petram PVC supply has a huge inventory of Sch 80 PVC and CPVC parts.