Use Bronze 45º Street Elbows for cold and hot plumbing, heating and pneumatic systems and marine construction.Bronze fittings have an outer surface that is rough in feel and appearance, almost like its covered with sand. Thats because bronze fittings are sand cast, and then machined. Bronze elbows are used for tight seals when joining two pieces of pipe at an angle and for their excellent resistance to harmful corrosion. These machined bronze street elbows feature female NPT threads on one end and male NPT threads on the other.Threads are tapered "NPT," which stands for "National Pipe Thread."