I would like to throw this in. The people are not talking about using refrigerant. They are referring to using the oil for the systems. R-12 and R134a are 2 completely different refrigerants and the oils are different. They are not compatible with each other.

I would strongly advise using oil for R12/22. R134a uses PAG oil. It does not seem to have the viscosity of R12 oil and I bekieve it will not do what you want in the retracts. Also PAG oil reacts with oxegen in the air and supposedly gell up. I have never witnessed this personally. But was told so in the schooling I got on theis refrigerant. So I believe this alone would count out PAG oil. Thirdly PAG oil is an irritant. You haven't livet until you get PAG oil on your face. It itches and burns at the same time. Hard to wash off also. So if for some reason one of you fella use this oil be very careful with exposed skin. Lastly PAG oil comes in I believe 3 formulas. And is dreadfully expensive. You can buy a gallon of R12 oil for the price of a half pint of PAG oil.

Stick with the R12 refrigerant oil. It is to my knowledge still readilly available through parts stores such as NAPA. Good luck with your retracts. Oh BTW I believe Rhom-Air is out of business.

Mark Shuman