Master System/Power Base Converter regional lockout?

[Tupin]

I've noticed it's pretty hard to find Master System games around here, but I found a site where all they have is European games, and I was wondering a few things.

First, do both European/American carts/cards work on an American Power Base Converter/Master System? Secondly, is there any difference in packaging between the European and American games?

[Policenaut]

All European carts and cards barring a few titles (Codemasters games and Back to the Future 2, New Zealand Story, Operation Wolf, Xenon 2, James Bond) should work on your US SMS. The packaging for European SMS games is noticeable as they are multi-language in the game description in the game insert, (most of the) the manuals have this multi-language description and have this landscape pattern printing whilst most of the US are portrait pattern printed.