attaché case 
noun
A small, flat, rigid, rectangular case used for carrying documents.In the early morning of April 29, 2002, a man in a white polo shirt carrying an attaché case came out of a two-floor apartment in a middle-class subdivision in Antipolo....
- Dressed in a dark business suit and carrying a black attaché case, he might have passed for an attorney returning from a late lunch.
- On the evening of December 4, he was stopped by demonstrators as he was leaving an office building in East Berlin carrying an attaché case.