The stainless steel is not absolutely rustless. It is just rust-proof in the proper condition. * For the indoor decoration or furniture, stainless steel 201 or 304 (SUS201, SUS 304) can be used. But Type 201 should only be kept in the dry condition. * For the outdoor condition with the polluted air, in the extremely humid environment, or somewhere with salty vapor, such as by sea or swimming pool, Type 316 or 316L should apply. * To bear the big load, the carbon steel is a good choice. Its finish can be Zinc plating or paint coating, varying in the environmental conditions.