The Hartland Controls HCT-03J2BB07 Transformer is a foot-mount control transformer designed to provide a reliable 24V secondary output from a 277V primary supply. It works by using electromagnetic induction to step down incoming voltage for safe, stable operation of low-voltage controls. Commonly used in HVAC equipment such as air conditioners, heat pumps, furnaces, and control system... https://www.partshnc.com/hct-03j2bb07-hartland-controls-pri-277v-sec-24v-75va-foot-mt