The Emerson Flow Control (Alco) 097379 FF444-V4-DRF Pressure Control is a precision control device designed to monitor and regulate refrigerant pressure in HVAC and refrigeration systems. It works by sensing system pressure and automatically opening or closing electrical contacts when preset pressure limits are reached, helping protect critical components and maintain efficient operat... https://www.partshnc.com/097379-emerson-flow-control-alco-ff444-v4-drf-pressure-control