- Seamless pipes and tubes (3)
- Pipes, seamless steel (2)
- Tubes, seamless steel (7)
- Tubing, mechanical or hypodermic sizes: cold drawn stainless (5)
- Welded pipe and tubes (5)
- Conduit: welded, lock joint, or heavy riveted (2)
- Tubes, wrought: welded or lock joint (2)
