This specification covers round, square, rectangular, and special shape electric-resistance-welded carbon and alloy steel mechanical tubing produced by hot- or cold-rolling. The types of tubing covered here are: Type 1a, as-welded from hot-rolled steel (with mill scale); Type 1b, as-welded from hot-rolled pickled and oiled steel (mill scale removed); Type 2, as-welded from cold-rolled steel; Type 3, sink-drawn hot-rolled steel; Type 4, sink-drawn cold-rolled steel; Type 5, drawn over a mandrel; and Type 6, special smooth inside diameter. Heat and product analyses shall be made to determine the percentages of chemical elements, to which the steel specimens shall conform to. Tubing shall be free of injurious defects and shall have a workmanlike finish. When specified, tubing shall be coated with a film of rust retarding oil before shipping.