我公司生产的蝶形螺母螺纹规格为M3-M24、保证扭矩为工级，用Q235钢锻制成的***为半圆形的A型和B型蝶形螺母。表面电镀处理，可参阅(GB/T5267.1-2002,ISO4042:1999,IDT)ISOgeneralpurposemetricscrewthreads-Tolerances-Part2:Limitsofsizesforgeneralpurposeexternalandinternalscrewthreads-Mediumquality,MOD))