Single-speed fans (not speed-controllable) provide spot cooling where space is limited. All AC units are rated at 60/50 Hz (50 Hz operation will decrease CMF by approximately 20 percent ). Oblong fans are good for unique mounting requirements. Optional fan guards and cord sets available separately. UL and C-UL recognized component, CE certified, and RoHS compliant. Note: sleeve-bearing fans must be mounted for horizontal airflow only. Ball-bearing and zero-friction fans may be mounted in any position. Cast-aluminum housing; driven with impedance-protected shaded pole or thermally protected PSC motor. Fan with terminal connection requires cord set not included