I'm not sure. I mixed my own this time because pre-mixed bags are really expensive in 1 liter bags and 1 gallon bags last too long. This way, I can mix as much or as little as I need. Plus, I get to mix warm tone, or ones for different uses. I bought my raw chemistry from various places when I had to order something else. Surprisingly, B&H and Adorama carries them (they all come from Photographers Formulary) and shippings are much cheaper.