Spring Return Direct Coupled Actuator, Two Position, SPST Control Signal, 100-250Vac, 88 Lb-In Torque, 2 Internal Auxiliary Switches, 45 Second Nominal Driving Time, 20 Second Maximum Spring Return, Nema 2 Rated, Crank for Manual Operation, 3/8"-1.06" Round or 3/8"-11/16" Square Damper Shafts, Self Centering Clamping Adapter, 5-95% RH Non Condensing Operating Humidity Range, -40-140 Degree Temperature Range, Enclosed Screw Terminal Strip