Ac heater control valve

There are replacements that function the same but look different. I used one, it doesn’t have a mounting flange, so I zip tied it to the heater hoses. The part numbers are UAC 1021 and UAC 1022. One flows with the vacuum on and one flows with the vacuum off. I don’t remember which is which and which which of them is correct for us. I will see if I can find a part number on mine.