what size posters are allowed for a concert?

I didn't see anyone with posters made at home.

They did not have posters for sale at the event. They did have hats, cd's, shirts, picks, and sweatshirts. I'm sure it very's event to event. As far as something you bring. nobody brought their own and the band did not make time for getting signatures. The event has guidelines for what is acceptable to bring into the event. Should have a link on line when you buy your tickets