Male BRASS UNION OD X NPT

A "Brass Union OD x NPT" fitting is a brass connector that joins two pieces of tubing or a tube and a pipe thread. It uses a compression union on one end for attaching to tubing (specified by its Outside Diameter, or OD) and a National Pipe Taper (NPT) thread on the other end for connecting to a pipe. These fittings are commonly used in plumbing, HVAC, and industrial applications.