材质 
M3
0.5
2
1.75
1.733
1.58
1.52
1.2
M4
0.7
2.5
2.25
2.303
2.08
2.02
1.5
M5
0.8
3.5
3.2
2.873
2.58
2.52
2
M6
1
4
3.7
3.443
3.08
3.02
2
M8
1.25
5.5
5.2
4.583
4.095
4.02
3
M10
1.5
7
6.64
5.723
5.14
5.02
4
M12
1.75
8.5
8.14
6.863
6.14
6.02
4.8