XV | | | | | base metals and articles of base metal |
| 73 | | | | articles of iron or steel |
| | | 730429 | | Casing and tubing, seamless, of iron or steel, of a kind used in drilling for oil or gas (excl. products of cast iron) |
| | | | 73042910 | Casing and tubing of a kind used for drilling for oil or gas, seamless, of iron or steel, of an external diameter |
| | | | 73042930 | Casing and tubing of a kind used for drilling for oil or gas, seamless, of iron or steel, of an external diameter > 168,3 mm, but |
| | | | 73042990 | Casing and tubing of a kind used for drilling for oil or gas, seamless, of iron or steel, of an external diameter > 406,4 mm (excl. products of cast iron) |