J&D Manufacturing’s PM Panel Fans featuring the JD-Drive are a game changer. They are available in 50", 55", & 60". Using only basic 0-10 volt control relays, this fan can efficiently operate at nearly any speed which allows uniform air recirculation even when on beginning stages, enabling all fans to run at low speeds, and eliminate dead or turbulent spots that are often created with full on/off fan stages. The high performance of the PM Panel Fan, means fewer fans are required and the incredible efficiency of 37.7 CFM/Watt when run at lower speeds can save you up to 75% energy savings over traditional fans.