6 Steel pipes; pipes of metal; elbows of metal for pipes; pipe muffs of metal; junctions of metal for pipes; gutter pipes of metal; drain pipes of metal; branching pipes of metal; clips of metal for cables and pipes; collars of metal for fastening pipes; reinforcing materials of metal for pipes; masts of metal; casks of metal; soundproof booths, transportable, of metal; penstock pipes of metal; water-pipes of metal; building materials of metal; posts of metal; rivets of metal; containers of metal for compressed gas or liquid air; tanks of metal; containers of metal for storing acids; taps of metal for casks.