The Combined Nomenclature (CN), v1:2018
9406 90 38: Buildings, prefabricated, whether or not complete or already assembled, made entirely or mainly of iron or steel (excl. mobile homes and greenhouses)
https://www.dst.dk/en/Statistik/dokumentation/nomenklaturer/kn?id=bdccfab4-a71c-4f32-8b96-d3d9ed56013c