If you have an older car it may have R12 refrigerant in the air conditioner system. You can still buy R12, but it is very expensive. If you are ready to convert your system to R134, here is a brief explanation of the procedure with a few insider tips to help you. To begin you will need a conversion kit with all the necessary materials. It will include: 2 new adapter fittings, 2 -3 cans of R-134, and a hose with adapter. Once you have all the materials, you can begin the process. The first thing you have to do is have the R12 recovered with a refrigerant recovery machine. (It is illegal to just open the valve and let it out in the air.) Now that the air conditioning system has no pressure, it is time to install the new valve kit. At this point some people freeze up (no pun intended) because they are afraid of mixing up the adapters on the high and low pressure ends. Don