The Combined Nomenclature (CN), v1:2018
8405 90 00: Parts of producer gas or water gas generators and acetylene gas generators or similar water process gas generators, n.e.s.
https://www.dst.dk/en/Statistik/dokumentation/nomenklaturer/kn?id=97dd4f6e-1b47-43b5-8532-380d3d1b7c2f