Freeze 12 is not R12. It is a blend of R134a and other gunk that allows it to work (arguably poorly) in an R12 AC system. Unfortunately a lot of places won't touch the stuff to flush since it also gunks up their recovery machines and contaminates any recycled refrigerant they have. Why didn't you just get plain old R12 in the first place if you're considering buying it now . Get the EPA license (or take it to a shop) and stick with true R12.

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TC
Current stable:
- 2004 Mazda RALLYWANKEL
- 2007 Saturn sky redline
- 2004 Explorer...under surgery.

Past: 135i, GTI, 300E, 300SD, 300SD, Stealth