Features. Coupling for connecting two pipes going in the same direction. Female National Pipe Taper NPT threads on both ends for connecting two male threaded pipes. Made from steel for greater rust resistance than iron. NPT threads for creating tighter seals than straight threads. Galvanized finish. Size - 0.38 in.. Dimension - 0.8 x 0.8 x 1.2 in.. Item Weight - 0.1 lbs.