The Caleffi Z-One Z47 2-Way Valve and Actuator Set with 18" Leads & AUX Switch is used to automatically shut-off the flow or redirect hot and chilled water in hydronic heating and air conditioning systems. The high temperature and high close-off performance characteristics of these zone valves, combined with compact size, makes them suitable to fit inside baseboard or directly in fan coil units. The Caleffi Z-One Z47 2-Way Valve and Actuator Set with 18" Leads & AUX Switch has a CV of 7.5.