A concentric reducer is used to join pipe sections or tube sections on the same axis.[1] The concentric reducer is cone-shaped, and is used when there is a shift in diameter between pipes.[1] For example, when a 1" pipe transitions into a 3/4" pipe and the top or bottom of the pipe doesn't need to remain level.[2] This pipe reducer may be used when there is a single diameter change or multiple diameter changes.[1] Unlike eccentric reducers, concentric reducers have a common center line. Concentric reducers are useful when cavitation is present. [2] Eccentricity occurs when the centerline is offset.