<<������I don't have envirosafe in my van, but I have put it
in a '92 Cherokee and a Saab 900 with good results. It cools well and
the high side pressure is less than with "freons". For me the main
attraction is that you don't need to change the oil when you start from
an r-12 system.>>
������
Here's the deal with the R-12A refrigerants.

Their bases are either derived from propane or butane.

Notice I said "bases", and this doesn't mean that they are filling the
AC lines with 100% butane or propane.

I think about it this way.

My butt is sitting right above 18 gallons of gasoline, and right in
front of a sausage shaped tank of propane.

If something was to happen while driving my Van I'm a time bomb anyway,
so if I'm going to go, I'm going to go BIG.

I don't even think about it, and am not really even concerned.

The vents are blowing 38 degree's, the  R-12A doesn't leak at all  like
the134 would, and offers no threat to my old antique compressor or other
original AC components with the off the wall operating pressure's of the
134.

And the best is I didn't lose 20% of the possible cooling capacity of my
system using the 134 alternative.

And I'm very happy with that.

The R-12A I'm using is Red Tek.