3521 Light stainless steel framing (0) Light stainless steel framing, principally of stainless steel sections, the sections framed together to form structural and non-structural assemblies of floors, walls, partitions, trusses, beams, etc., forming part or all of the frame of a building, fabricated off and/or on site 3522 Stainless steel pipe framing (0) Stainless steel pipe as framing for partitions, walls, etc.