The Combined Nomenclature (CN), v1:2023
9406 90 38: Buildings, prefabricated, whether or not complete or already assembled, made entirely or mainly of iron or steel (excl. mobile homes, greenhouses and modular building units)
https://www.dst.dk/en/Statistik/dokumentation/nomenklaturer/kn?id=6288e2f3-11bf-4206-90bf-a3b6f6ebbc4d