For on/off, fail-safe control of dampers in HVAC systems. Actuator sizing should be done in accordance with the damper manufacturer’s specifications. Control is on/off from an auxiliary contact, or a manual switch. The actuator is mounted directly to a damper shaft from 1/4” up to 1/2” in diameter by means of its universal clamp, 1/2” shaft centered at delivery. A crank arm and several mounting brackets are available for applications where the actuator cannot be direct coupled to the damper shaft.