As Bill pointed out, the bottles that say Prestone aren't conventional green.
Prestone's conventional green is called Prime.
O'Reilly's conventional green is what it says.
Well, this might be a little confusing. The old green stuff that is called green is more like a mix of yellow and green, slime sort of ? (uff, was that bad language?) And the new yellow is more like a see through yellow, but with a green tint on it. So, it is easy to be confused. What I mean is that I would not be surprised if someone think the new yellow stuff is just a variety of the old green one.