Also known as reducing elbows. A type of piping fitting used for connecting pipes of different diameters. It is further divided into concentric reducing elbows and eccentric reducing elbows. See pipe fittings.

eccentric reducer (odd size pipe)

eccentric reducer (reduced diameter pipe)

Diameter reducing pipe materials include stainless steel reducers, alloy steel, carbon steel reducers in sizes, and 20# steel reducers such as q234q345.