The Combined Nomenclature (CN), v1:2019
3813 00 00: Preparations and charges for fire-extinguishers; charged fire-extinguishing grenades (excl. full or empty fire-extinguishing devices, whether or not portable, unmixed chemically undefined products with fire-extinguishing properties in other forms)
https://www.dst.dk/en/Statistik/dokumentation/nomenklaturer/kn?id=ec3af576-673e-42d6-892f-12eb18291831