ISO 683-4:2016 gives the technical delivery requirements for semi-finished products (e.g. blooms, billets, slabs), bars and wire rod, manufactured from the free-cutting steels listed in Table 2 and supplied in one of the treatment conditions given for the different types of products in Table 1, rows 2 to 4. It covers three groups of free-cutting steels for mechanical purposes as listed in Table 2, namely a) not intended for heat treatment, b) suitable for case-hardening, and c) suitable for quenching and tempering. Free-cutting steels are often used as bright bars. For these products, refer to ISO 683‑18. In special cases, variations in these technical delivery requirements or additions to them can form the subject of an agreement at the time of enquiry and order (see 5.2 and Annex B). In addition to ISO 683-4:2016, the general technical delivery requirements of ISO 404 are applicable.