ACDelco GM Original Equipment A/C Expansion Valves are metering devices that control the flow of refrigerant into the evaporator and are GM-recommended replacements for your vehicle’s original components. The expansion valve meters the flow of liquid refrigerant based on the evaporator core temperature, keeping it just above freezing. This original equipment A/C expansion valve has been manufactured to fit your GM vehicle, providing the same performance, durability, and service life you expect from General Motors.