Many board games use square cards that are 70mm × 70mm, about 2¾″.
Are there any that use larger square cards? If so, what's the largest square card that is in use?
I'm mainly interested if there are any square cards larger than 70mm. I'm working on a game that needs square cards, and 70mm isn't big enough. The company I'm at wants to use sizes of cards that are already in use, where possible.
The reason the cards need to be large is because people are putting tokens on top of them when they're in play, not because they have to display much information.