Karl Dungs Inc. Actuators are designed to operate dampers, butterfly valves and similar devices. Models are available for a variety of torques from 16 in. lb. to 450 in. lb. and control methods including two-position, position proportioning with slide-wire feedback, potentiometer proportioning and current-to-position proportionin. All models are UL listed and CSA Certified. Two position, spring return. 90-deg & 180-deg Clockwise rotation when power is applied, actuator returns counter-clockwise to 0-deg on power interruption.