… paper), and the like, used or unused, other than those of heading 49.07. …
Explanatory notes
… and the like, used or unused, other than those of heading 49.07. This heading covers the following products used … bearing a postmark, but no postage stamps, used before the introduction of postage stamps. (D) Postage stamps stuck on envelopes or cards , including “ first‑day covers ”, which are envelopes, usually …