The Danfoss 082H5006 N/O Actuator 24V AB-QM is an electrically operated normally open actuator designed for compatible AB-QM pressure-independent balancing and control valves in HVAC hydronic systems. It works by receiving a 24-volt control signal to precisely regulate valve position, controlling the flow of heated or chilled water through air handling units, fan coil units, and other... https://www.partshnc.com/24v-no-ab-qm-actuator