Formal duds

TUX

Think of what a groom or a James Bond might wear to a black-tie event—it’s often black with a bow tie.

Formal duds" is a casual way to refer to fancy clothing, where "duds" is slang for clothes. The answer "TUX" is short for "tuxedo," the classic formal suit often worn to black-tie events. The clue plays on the contrast between the informal word "duds" and the high-end nature of a tuxedo, making it a clever but straightforward hint.