The Combined Nomenclature (CN), v1:2024
4907 00 10: Unused postage, revenue or similar stamps of current or new issue in the country in which they have, or will have, a recognised face value
https://www.dst.dk/en/Statistik/dokumentation/nomenklaturer/kn?id=ff35b666-b08b-41b5-bea1-78e213f89ca8