John GuestSpeedfit 3/8 Inch Compression Female Connector, Push to Connect Plastic Plumbing Fitting, White, PSEI6012U9P

So far, so good! No leaks! Perfect attachment to go with a 3/8 tee stop valve for my water filter.

Easy to install, works great and no leaks

After multiple trips to the local hardware stores, I finally found what I actually needed on Amazon. I recently moved into a new house and had an RO installed the day after we moved in. I needed to hook up my RO to my refrigerator water supply line and was having no luck whatsoever finding the hardware to get it done. My RO is the APEC RO-HI (purchased from Amazon) with the 3/8" tubing for faster water dispensing. On new house builds (at least in AZ) the builder is installing 3 standard water valves under the kitchen sink area. 1 = hot, 2 = cold, 3 = refrigerator water line feed. By default the builder will use a 3/8" to 3/8" compression hose to connect valve 2 (cold water) to valve 3 (fridge water feed). I tried finding the standard tube compression fittings with nut & ferrule but I just couldn't seem to find the right part. I finally searched Amazon and found this 3/8" female compression to quick connect push-in tubing connector and it was exactly what I needed. The connector screws onto the standard 3/8" compression male adapter of a water valve and the other end accepts my 3/8" RO water line tubing. From the attached picture, you can see the connection to valve 3 (fridge water supply feed) on the right. This connector is attached directly to the water valve. You can't see it, but I cut a small piece of tubing and attached this connector to a 90 degree connector to eliminate extra strain heading up to the additional T connector on the clear tubing. The clear tubing is the filtered RO line going to my RO faucet. By adding the T connector, I have good water going to the RO faucet and into valve #3, which feeds my fridge water source. I added some Teflon tape to the valve 3 male end and hand-tightened this connector. No leaks and perfect result. Highly recommend this product if you need to connect your 3/8" RO tubing to your standard 3/8" compression male valve. A++

Had to replace a leaking plastic fitting and this one is 100x better quality.

This works a charm to go from angle valves (3/8" compression) to the typical push to connect lines. Used this to connect a Reverse Osmosis filter system to the customary angle valve. However, I had to use an adapter to reduce the PTC side down to 1/4".Oddly the description does not mention the size of the PTC connection, which delayed my installation further as I waited for the reducer. Finding this type of small piece at the big box stores is a bit hit and miss, and I was not in a particular hurry, but still would have been nice to know connection type on both sides. One star off for lack of description.

perfect for connecting my upgraded 3.8 line to my shutoff valve on the RO.

No idea why these aren't available at a local hardware store, but I got it here and it works perfect.

Speed fit indeed. No leaks so far, a little pricey but I'll take it for the functionality.