Description

The Aqua-Flo 91431150 is the union nut for 2 in. pump unions. It is the threaded collar that draws the union half up against the pump port and holds the joint together.

Why it is a wear part

Union nuts take the whole clamping load of the joint and they live outdoors. Between UV making the plastic brittle and the habit of reaching for a wrench when a joint weeps, they crack at the thread more often than any other piece of the union. A cracked nut cannot pull the faces together, so the joint keeps seeping no matter how far it is turned.

What you are buying

The nut only. If the union o-ring is flattened or the tailpiece is damaged, those are separate parts. Replacing the nut lets you fix the joint without cutting into plumbing that is otherwise fine.