24unf螺纹底孔直径网！
24螺纹底孔多大
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1 4-28unf螺纹底孔和螺距
12-24unc螺纹底孔
1/2 20unf螺纹底孔
m24螺纹底孔直径
1/4-20unc螺纹底孔大小
1/4-20unc-2b螺纹底孔
0.19-24unc-2b螺纹底孔
3/8-24unf螺纹底孔
