The ZoneFirst MST 24V Motor Assembly is a two-position motor designed to control HVAC zone dampers, registers, and diffusers. Operating at 24V AC and 6 watts, it opens or closes compatible dampers through an SPDT control and automatically stops power when the selected position is reached. It is suitable for AOBD, AOBM, and IOBD dampers, as well as older TAT registers and diffusers. Th... https://www.partshnc.com/mst-zonefirst-24v-motor-assmfor-aobds