The main reason I offered it as a suggestion was because of the price. I do know there are gases which are supposed to be a 'drop in' replacement for R12, but IME they tend to be expensive. Before I had the Celica regassed I rang a few local auto a/c engineers. Only one gave me a quote for the alternative gas, which he didn't have in stock, and he wanted over £110. I then reached the guy who was refilling in the way I describe. Initially I was very sceptical about it, but he assured me it did work. What's more, he only wanted £60, which is about the local going rate for a 134 regas. When I took my car to him, I got chatting to another customer who'd come in to pick up a R12 a/c yank tank that had just been regassed with 134. It was he that convinced me more than anything else to try it, as he had another R12 a/c car at home that had been regassed with 134 over 2 years before, by the same guy using the suggested method, which was still working well. Another point in it's favour, is the fact that because it uses 134 gas, there is no reason for the price of a regas to increase, which could happen with replacement gasses as the number of R12 a/c cars that can use it reduces. Mike.