Could you be thinking of the difference between TX (Tri-X) and TXP (Tri-X Professional)? Those are different emulsions. I think 35mm Tri-X is always TX and sheet film sizes are always TXP, but both come in 120, and it might be the case that the availability of TX vs. TXP in 120 sizes could be different in the US and Europe. Add to that the issue of grey market sales, and it makes the whole matter even more complicated.(posted 8714 days ago)