1/4" tube OD check valve

These work extremely well. I use them to prevent water siphoning out of bird baths and fountains.

I tried hooking one of these up backwards and my flow stopped. Hooking it in the correct way the water seems to flow the same as before. I call this a success. If it lasts over a year then great! If not then well that's what I get for buying cheap.I may re-review if I notice they stop working at some point.Side note:Not sure why people think they can supply enough pressure with wee little human lungs. Obviously the psi in a water hose is going to be higher than a set of lungs can push.If someone tries to say they cant blow through it and gives a bad review, ignore it and keep scrolling. If you're not supplying measurable data and saying its crap then do us all a favor and stay out of the reviews. Thanks.

Works perfectly!

Work as designed…. Hope it lasts

Good

Im hoping that these will allow r.o. systems to drain without allowing water to back up and out the vent hole on the r.o. faucets.

Immediately broke in half when any pressure was applied. I tried two different ones thinking it was a fluke but same thing. Maybe 10psi max

Work great good price.