Heading 9870 covers: (1) articles that were imported from Canada and are being returned to Canada; (2) exhibits being sent to Canadian public museums or institutions; and (3) items destined for the Canadian Governor General. Each transaction type has its own eligibility conditions, and the goods must meet the specific criteria for the applicable provision.

It applies only to the three narrowly defined transaction types described in the heading — not to general commercial exports to Canada. Standard commercial exports to Canada are classified under their normal commodity headings, not under 9870.