Clear UPVC Check Valve, 1inch Slip Swing Full Port Utility Double True Union Check Valve, UPVC No-return Valve, Sch80 Socket End Pool Ball Check Valve for Backflow Prevention

Used this for my pool overflow and it works fantastic. Would buy again for sure.

I installed these instead of the plastic flap one-way valves after a 200 gallon water leak. I use them on a sump that is about 200 gallons lower than the top of my 650 gallon main tank. So if we have a power outage and we are away we really need a reliable valve. I use them on a pretty dirty Oscar fish tank and the pumps do pump a lot of solids so the valves get a little bit sticky if you let them. I have found that if you turn off and on the flow so as to let them close and open a few times every once in a while it keeps them free of dirt that would impede them closing easily. And of course they are cleanable so I can just take them out of service give them a quick scrubbing and voila we are in business again. If you are just pumping clean water all I have described is probably not going to be an issue. But for a big fish tank these are perfect. Haven't tried them with salt water.

This seems like great quality. It's heavy duty and you can completely take it apart to clean, and mine came with extra rubber seals. Not only is it a check valve, but it's also a union, for easy removal of the water pump in my usage. I used PVC primer and glue, plus Teflon tape on the threads, with no leaks.

Very good check valve, but not great that 2 of 3 started failing within 2 months of use. The rubber gets grimy quickly. Granted, in my application for a saltwater aquarium, check valves are known to fail quickly. I haven't seen them fail that quickly though. For normal applications, I am certain they would perform great. Only reason it is not 3 stars versus the 4 I gave it is because of the abuse from saltwater.

The valve prevents back-flow, but is extremely noisy! I have it installed on my return pump for my reef tank. Going to have to switch to a swing type in order to mitigate the noise.

This worked 100 times better than the check valve home depot sold!! yes definitely recommend and def would re buy.

I wish more check valves were designed with this see-thru UPVC. It was great for teaching the students. They could see how the valve actually works.

This failed after 4 months which renders it questionable as a backup to my siphon breaks.