The expansion valve is typically found on all 911 models through 1983 and all 930 models through 1979. This valve has two copper tubes. The top tube is hermetically sealed and has a coil (pig tail) on the end. The pig tail is gets clamped to the top of the evaporator outlet pipe. The second copper tube exits the back of the valve. This second tube is the external equalization tube. It has a flare fitting and attaches to a fitting on the evaporator outlet tube. The Kuehl Expansion Valve is both R12 and R134a compatible.