Barbed Pipe PEX Insert Adapter Elbow, Brass, 1/2-In. Barb x 1/2-In. Female Pipe

We used these fittings at work. Have had numerous leaks. And if we tighten them to stop the leaking, the conical gasket rips. It is NOT a replaceable part per the manufacturer. So we end up having to replace the entire part. We will never use these again. So far, we've had at least 6 of them go bad. Company should sell a pack of replacement gaskets. :(

(I am very experienced.) I have installed 4 of these. They all dripped unless I secured the tubing completely perpendicular to the 1/2" male NPT piece to which I was connecting. This worked for two of them for the two that I used on a small hot water heater. The other two I used on a Delta shower valve to connect the hot and cold supply to the horizontal 1/2" brass NPT connections. I secured them to vertical studs a couple feet away to get that straight shot, and tightened the heck out of them to stop the remnant drip. That was in a rental house and thank goodness there was closet access, and I had not buried the fitting in a wall. A year or so later I get a call from the tenant that the plaster ceiling below was dripping and starting to crumble on the floor. I checked the pipe below the fitting and wrapped my hand around it. It took a minute for a drop to form, but that's what did it. -- By experimenting I realized that with just slight side pressure on the pipe, even the tightest of these fitting drip. And, like one of the reviewers said, the plastic nut broke. I wouldn't buy anything like this until it is redesigned, and has a brass nut that will handle tightening. BTW, I left the two on the water heater because it's at my house where I see it everyday, and it is over dirt--in case it drips. Caveat--I installed these in spring, 2016; if the problem has been solved, please let me know.