The Cleveland Controls AFS-460-137 is a high-quality DPDT (Double Pole, Double Throw) air pressure switch designed for HVAC systems and industrial applications. It operates within a pressure range of 0.4 to 12 inches WC (water column) to detect positive, negative, or differential air pressure. This switch is ideal for monitoring air flow, fan operation, and filter status in systems su... https://www.partshnc.com/afs-460-137-cleveland-controls-412-wcmr-dpdt-air-switch