((a)) Balloting materials under the Uniformed and Overseas Citizens Absentee Voting Act (individually or in bulk)—
((1)) shall be carried expeditiously and free of postage; and
((2)) may be mailed at a post office established outside the United States under , unless such mailing is prohibited by treaty or other international agreement of the United States.
((b)) As used in this section, the term “balloting materials” has the meaning given that term in section 107 of the Uniformed and Overseas Citizens Absentee Voting Act.