This standard is no longer an American National Standard or an ASME-approved standard. It is available for historical reference only. This Standard contains complete general and dimensional data for metric series hexagon socket head cap screws in sizes from 1.6 mm to 48 mm and for metric series spline socket head cap screws in sizes from 1.6 mm to 8 mm. Also included are appendices covering drill and conterbore sizes (Appendix I), drilled head dimensions (Appendix II), formulas for dimensions (Appendix III), ISO dimensional variations (Appendix IV), part numbering system and preferred sizes for government use (Appendix V), and thread dimensions (Appendix VI). The inclusion of dimensional data in this Standard is not intended to imply that all of the products described are stock production sizes. Consumers should consult with manufactuers concerning lists of stock production sizes.