Rotron Centraxial Blowers have an impeller that, unlike the Centrifugal Blower, achieves a substantial portion of conversion of velocity energy to pressure energy within the impeller itself. This impeller is much less dependent upon a scroll or housing and may therefore be operated without a scroll or housing with a relatively small loss of in performance and efficiency. The impeller function is similar to a turbine impeller. A benefit of this kind of product is that, when operated with a housing unit, the blast direction may be changed relatively easily. Centraxial Blowers come in a variety of voltages and frequencies. Most units are available with an optional internal Fan Performance Sensor (FPS) or external Low Speed Warning Device (LSWD).