I have had two of these valves fail due to splitting and cracking of the threaded pipe connections. The valve leaks at these connections and you cannot tighten the male adapters enough to stop the leaks. Whatever it is made of, the PVC is much harder. Just hand tightening the screwed connection is enough to split the body of the NEW valve. I am looking for another one. It should have four unions instead of two! The valve is also very awkward and hard to operate. The glass "bottle" sight glass always leaks too.