John Guest Speedfit 3/8 x 3/8 x 1/4 Inch Angle Stop Adapter Valve, Push to Connect Plastic Plumbing Fitting, ASVPP1LF

I ordered this valve to replace the the plastic T adapter that came with a water filter system

This valve worked perfectly while installing an under-sink 6 stage filter, and thats saying something, because the valve provided by the filter manufacturer did not.

Works like a charm! This is a quality product. Note that the valve only turns on/off the flow from the divider. It doesnt switch the flow of water between the two outputs.

Some of these come with different sized inlet/outlet and you can use an adapter to downsize I believe, but if you have a Watts RO system with the crappy brass small/thin rounded handle that needs to be turned 3x or more from full close to open, this replaces it just fine with no adapter needed if your need is 3/8 on both sides. Quarter turn and you are done. Works great!

Does the job very well.I feel confident to use them without worrying about leaks. Hard to see when they are on and off but its not a big issue.

Had a mountain plumbing instant hot water unit under my sink that started leaking badly (dont buy anything from mountain plumbing, their products leak and they dont stand by them!). In the process of disconnecting, found that my shutoff valve was not working. Shut off main water, removed the non-working valve and discovered that three pebbles had somehow gotten into the line and were preventing the valve from shutting off. Once out of the way, valve was re-installed and fine, but I needed to replace a t-joint feeding cold water to my cold-water filter (shown in upper right of my picture). I wanted a t-joint with a shutoff valve and this John Guest part fit the bill perfectly. Installed it and all is good now; including that I needed to use the shutoff function and its doing its job perfectly, ie, no leaks.

Perfect!! Buy this! I was looking for right connetor something does not leak at all and this is it! I bought METPURE brand connector first but water was keep leaking so I returned and tried this one and i am happy about the result! It has a rubber band inside of the connector so water does not leak at all if you tightened well.

Needed it for my Aquapurr automatic cat waterer. Im so happy with how everything worked out.

Thank you for selling this part! I was trying to install a under sink water filter and it came with 1/2 by 1/2 x 1/4 adapter, didnt work with my 3/8 fittings at all! I kept getting leaks. This solved every leak problem and made installation so simple. Best buy ever!

All I can say is OMG I wish I had started with this valve instead of with the metal one that got all corroded and nasty and was so hard to tighten in that small space under my sink!!! Love it - installed VERY quickly and works perfectly, so when I am changing out my water filter stuff, I can easily shut the water supply off.