Any drug or device intended for export shall not be deemed to be adulterated under this part if it satisfies all of the following requirements:
(a) It accords to the specifications of the foreign purchaser.
(b) It is not in conflict with the laws of the importing country.
(c) It is labeled on the outside of the shipping package to show that it is intended for export.
If the article is sold or offered for sale in domestic commerce, this section shall not exempt it from any of the provisions of this part.