BioTek Marine Clear PVC Flapper Check Valve With Slip Unions
Flapper style easily opens and closes.
Check valves allow water flow in only one direction and are used to prevent back flow and siphoning in the event your pump(s) turn off. They are commonly used on return pump outputs to prevent water overflowing the sump in the event of a power outage, pump failure or maintenance.
Slip x Slip
True union connection can be screwed and unscrewed for replacement of maintenance.