ECM Motor Diagnostic Tool ECM Evergreen Brushless DC Direct-Drive Fan and Blower MotorsReplace PSC motors in residential or light commercial HVAC systems. Provide operating cost savings and energy efficient alternative to shaded pole and permanent split capacitor designs. Not suitable for replacement of variable speed or X13 ECM motors.UL and C-UL Recognized.Enclosure: open Mounting: band Insulation: Class B Shaft orientation: horizontal Duty: continuous Speeds: 4 selectable, 1 constant low fan speed Quick-change voltage plug Reverse sensing technology