United States travel document
United States travel document, also known as the USCIS Travel Document since 2004, is a travel document issued by the United States Citizenship and Immigration Services (USCIS) to eligible non-U.S. citizen residents. It is a green passport-like booklet with the words Travel Document, a symbol, and other official wording in blue-gray.
Source: Wikipedia — United States travel document (CC BY-SA 4.0)