DIN 13-2 : 1999未知
ISO GENERAL PURPOSE METRIC SCREW THREADS - PART 2: NOMINAL SIZES FOR 0,2 MM, 0,25 MM AND 0,35 MM FINE PITCH THREADS - DIAMETERS FROM 1 MM TO 50 MM
出版：German Institute for Standardisation (Deutsches Institut für Normung)
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