Pipe fittings such as: bends, Tees, reducers, headers, valves, filters, strainers, heat exchangers, etc, affect the velocity profile in the downstream pipe. These profile distortions are known to affect the performance of flow meters. The magnitude of the effect depends upon both the severity of the distortion and the sensitivity of the meter (Ref. 1). One solution to these problems is to use long straight lengths of pipe upstream of the meter. Friction effects on the wall of the pipe will eventually extend to the center of the pipe to produce a fully developed velocity profile, which no longer changes with any additional pipe length. Unfortunately in certain applications this can take very long lengths (hundreds of diameters), which is often neither practical nor economic