Description

A compression nut is a threaded fitting component used in compression‑style plumbing joints, where it secures a ferrule (or “olive”) against tubing and a fitting body to form a sealed connection. When tightened, the nut compresses the ferrule onto the pipe, deforming it slightly so it grips and seals against both the tube and the receiving fitting surface. Made from brass, it provides corrosion-resistance. Because the fitting’s seal depends on compression of the ferrule—not on the threads—thread sealant is usually not required (and overtightening the nut can damage the seal).