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637 Other Restricted Matter

Materials that are nonmailable domestically are also prohibited in international mail. The restricted materials include, but are not limited to, intoxicating liquor; matter emitting obnoxious odor, motor vehicle master keys, odd-shaped items sent in letter-size envelopes, abortive and contraceptive devices, and certain building construction material. See IMM 135 and 136 for other general restrictions and prohibitions, and the Individual Country Listings in the IMM for specific country restrictions and prohibitions.