This International Standard specifies the technical delivery conditions for steel drill-pipes with upset pipe-body ends and weld-on tool joints for use in drilling and production operations in petroleum and natural gas industries for three product specification levels (PSL-1, PSL-2 and PSL-3). The requirements for PSL-1 form the basis of this International Standard. The requirements that define different levels of standard technical requirements for PSL-2 and PSL-3 are in Annex G. This International Standard covers the following grades of drill-pipe: - grade E drill-pipe; - high-strength grades of drill-pipe, grades X, G and S. A typical drill-pipe configuration is given, showing main elements and lengths (see Figure B.1). The main dimensions and masses of the grades of drill-pipe are given in both SI units (see Table A.1) and in USC units (see Table C.1). This International Standard can also be used for drill-pipe with tool joints not specified by ISO or API standards.