Designed to convert existing Dayton Centrifugal Upblast Exhaust Ventilator to an energy efficient, Electronically Commutated (EC) Ventilator. These completely assembled motor packages install easily and reduce energy use and cost. They also have variable-speed motors that include a potentiometer dial mounted directly on the motor eliminating the need for a speed control, allowing units to have a wide RPM range to customize to your facility.