Acdelco gm original equipment a/c expansion valves are metering devices that control the flow of refrigerant into the evaporator and aremended replacements for your vehicle’sponents. 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