Valterra 200-C20W PVC Swing (No Spring) Check Valve, Clear Blue, 2" Slip , White

Priced right.

Worked perfectly

Works like advertised. and is cheap... I did a home made solar pool heater on my roof and needed to prevent the water from streaming back via the pool filter resulting in diatomaceous earth inexplicably (at least at first) ending up in the pool.

Great

great item but did not fit so it was returned

This part broke after slightly less than a year in my pool system. Flapper totally disconnected in the body, largely blocking the flow. The previous one (from a quality manufacturer) last about 20 years. I will not buy this again’

We have three pumps installed in parallel now, a solar pump, a older variable speed to save AC power, and a bronto pump for hi flow needs. On the inlet side, these valves automatically prevent flow back through the inactive pumps without turning handles. On the outlet side, these prevent over pressure or leaks into the inactive pumps when opening baskets for cleaning. Note that you should use manual gate valves when removing pumps.

It is cool that it is clear, unsure how it will do in the sun but that feature is cool. However, right out of the package I take it to the sink and fill it with water, it leaks! It is not a 100% check valve. The volume of water in the valve leaked pass the flap gate in about 30 seconds. It was not a drip but a stream. This will not do.Also for those that want to keep it, please understand it must be mounted in the position in the picture. It cannot be mounted horizontally. and the water flow must be upwards. This may or may not be a deal breaker to your installation needs.