CV6R

Great quality check valves for a really reasonable price. Not much to these. Worked great for fixing my Keurig 2.0 K200 coffee maker which had a damaged air pump (very common problem I learned). Replaced the air pump and tested operation. Worked great but noticed water was being pushed into it, which is what caused it to fail the first time. Added one of these check valves in line and life is great now. Shame on Keurig for planned obsolescence.

Amazing value, works wonderfully! Gets the job done

The airflow control works just fine but due to the smooth tapered connectors, the hoses constantly slide off. I had to superglue the hose onto it

Perfect replacement parts

Here is an honest review from a verified purchase. I have been keeping aquariums for 40 years. These are among the best valves I’ve had. They work perfectly. Any review that says otherwise was written by someone that doesn’t know what they are doing or they were using them wrong. Simply slide a paper clip or toothpick into the opening and gently open the valve before connecting. After all you want a good seal to avoid water back flow. The air has air flows beautifully. They are easy to connect using some warm water on the tubing. They have nubs to keep the hose on. These are great valves. Don’t pay attention to negative reviews.

Just what I needed for piece of mind

Thank gosh for these! No more water going back to the air pump when power goes out. Have been using one for a long while now with no issues. Super easy to install, no extra noise, exact fit, and does what it should. I own a 75 gallon fresh water tank.

These were pretty cheap so I really wasn't expecting much and overall they are average. Yes, I saved money because just one at the local store is $5 buuuuuuut 2 out of the 6 were defective and made such a horrible whistling noise I thought my air pump was bad. The other 4 worked alright, they are a little tough to get the airline onto unless you're using the super flexible silicone kind. But I've had another one snap off at the neck when I was trying to change the line so durability is definitely limited. These fit standard airline tubing!

Got only 5 pcs

Good quality check valves. Only needed one but for the money got a load of spares! Functions as you would expect!

Work as expected, gotta have em in the fish room.

so far these have been amazing

Excellent one-way check valve.. although not recommended, I've used these on an CO² tubing and they actually work better than some CO² C.V's I paid twice as much for. Would STRONGLY recommend for normal air pump lines on the aquarium.