DIGITAL CONTROLLER INCLUDED IN THE BOX - NEW 9 POLE DIGITAL EC ‘BRUSH-LESS’ MOTORS - HIGHER FAN EFFICIENCY @ 7.85 CFM PER WATT - HIGHER LINEAR AIR FLOW OUTPUT THAN OTHER FANS - HIGHER STATIC PRESSURE OUTPUT THAN OTHER FANS - DETACHABLE, FULLY VARIABLE SPEED CONTROLLER INCLUDED - STURDY, STEEL HOUSING AND ABEC 7 BALL BEARINGS - 0-10V CONTROLLER COMPATIBLE VIA RJ9 OR RJ11 CABLE