Check Valve - Clear PVC Flapper - 1½" FNPT X 1½" MNPT

This clear flapper type check valve is used as a sight glass on an Edson Pump Out Hose and as flapper valves for controlling the flow of liquid in and out of the Edson Vacuum System transfer tanks. If required it can be used as a back-up flapper valve on an Edson Diaphragm Pump and it will insure zero back flow on a pump out hydrant. Made of clear PVC with Viton® elastomer for the flapper it has 1½" MNPT (Male National Pipe Threads) on the in-flow and on the out-flow 1½" FNPT (Female National Pipe Threads).(Viton® is a registered trademark of E. I. DuPont.)