This 2½” Sch 80 CPVC Pneumatic Butterfly Valve, EPDM, Double Acting, (FLANGE x FLANGE) is a butterfly valve with a pneumatic actuator on top for automatic control when compressed air is applied. the pneumatic actuator opens and closes when compressed air is applied to the respective ports. Butterfly valves are installed between a pair of flanges with falnge bolts. No gaskets are required, they are built into the valve face. CPVC is a higher temperature version of PVC and has better chemical resistances. EPDM seals provide effective sealing with resistances to several chemicals over a wide range of temperatures. Petram PVC supply has a huge inventory of Sch 80 PVC and CPVC parts.