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 < 406,4 mm (excl. products of cast iron)
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)
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 (excl. products of cast iron)