This part of GB/T 902 stipulates threaded studs (PD type) for arc stud welding with thread specifications M6 ~ M24 and threaded studs with shrink rod (RD type), and arc stud welding for M5 ~ M12 Use internally threaded studs (Type ID) and magnetic rings (PF, RF and UF types) for use with them. The product types stipulated in ISO 13918 are compared with Japanese standards, see Appendix A.