The KMC Controls CCE-3001 1-Stage SPDT Pneumatic Relay is a reliable control device designed to convert pneumatic signals into precise switching actions for HVAC systems. Operating at 30 PSI and compatible with 277V circuits, it enhances control of air handlers, rooftop units, and ventilation equipment. https://www.partshnc.com/cce-3001-kmc-controls-277v-spdt2202-dif