This International Standard specifies the profiles, diameter-pitch combinations, basic dimensions, tolerances, limits of size and designation for ISO miniature screw threads with nominal diameters from 0,3 to 1,4 mm. These threads are applicable to timepieces, optical instruments, electrical meters, measuring instruments, etc. The profiles and tolerance system for ISO miniature screw threads (S) differ from the profile and tolerance system for ISO general purpose metric screw threads (M). For the threads with nominal diameters from 1 to 1,4 mm designers shall decide to use ISO general purpose metric screw threads (M) or ISO miniature screw threads (S). The late one is shown in Annex A. The differences of miniature screw threads between the standards of ISO/DIS and some countries are shown in Annex C.