Outside menus are typically now flatbed print with thin plastic inserts I want to say it's really thin lexan, but I'm up really late. They are cheap and easy to change out the cost for an outside digital display is very high for a menu. Other option is you in case a TV but it doesn't have the NIT value that you need. I am interested in what you find because I do have a vendor that sells 6 mm LED signs but they're god awful expensive.