ZYAMY 4pcs Straight NPT Thread Adapter 3/4" FNPT to 3/8" Tube OD Push Fit Quick Connect Plastic RO Fittings Water Purifier Accessories

Quality products, but wrong size. They are not 3/4" FNPT to 3/8" OD. They are 1" FNPT to 3/8" OD.

I really wanted to like this product but I had to return it. It seemed well made but the connection to the hose garden hose fitting leaked spraying water everywhere. I verified that there was a washer inside. I tightened it up with wrenches. I tried a new washer. I even tried using plumbers tape but I still leaked. I even tried a different one from the package with the same results. Very disappointing. I have a similar product, 1/4” out instead of 3/8”, and it worked fine. No leaks. Amazon did accept my return.