... DIN7981, DIN7982, DIN7983 ASME B18.6.4 & SAE J933 specifications Self Tapping ScrewsDIN7971, DIN7972, DIN7973, DIN7981, DIN7982, DIN7983 ASME B18.6 ... repeated assembly and disassembly. There are three different kinds of self tapping screws: thread forming, thread cutting, and thread rolling. ... Type: Type A, Type B, Type AB, Type 1, Type 23, Type 25, Type Hi-low, Type F Material: Carbon steel ...