EIN, proof of your business address, Articles of Incorporation, Operating Agreement, Passport copy and letter of good standing (sometimes a business plan, but quite rare)
5 years ago it was ok to just show EIN as proof of address, however nowadays they often ask for an US phone number (real landline, not VOIP) + utility bill. After account opening you can change to a VOIP number.
If you have a nominee director things could be more complicated. I already heard a few stories that the nominee director had to show up by himself, too.
If you disclose yourself as UBO, then keep the "John Doe Summons" in your mind.