I don't know about this particular case, but a lot of times when one looks more deeply at two things that are the "exact same substance", one finds that they ma

I don't know about this particular case, but a lot of times when one looks more deeply at two things that are the "exact same substance", one finds that they may be primarily the same substance, but there are a number of surrounding details that are different driving the separate products. It could be different marker smells or dyes, or that there is a bit of lubricant additive in R-134a, etc...