Using a pressure sensor, vortex flowmeters measure the pressure pulses from vortices that come from the fluid passing a bluff body bar across the flow stream. A simple analogy of this phenomenon is that of a flag waving in the wind. The pulses are proportional to the rate of flow. Many users find the technology appealing because it has no moving parts. Because the meter body and vortex bar can be molded as one, this design is ideal for making meters for use in aggressive or high-purity applications.