Even the writer of this card, mailed in 1917 (with stamp and partial postmark), acknowledged it’s an ad card, but what a good ad card it is:  the somewhat generic American Express Travelers’ Cheques promotion then mailed out by individual banks (including long-gone Monroe County National) or from — as in this case — friend to friend.  As a side note, while Travelers’ Cheques must still exist, around here in Asia they are met with horror by merchants and banks.  Don’t even think of trying to use one.  Grade: 1