材质 
M10
1
19.6
4
17
16.73
0.5
M12
1.25
21.9
4.5
19
18.67
0.6
M18
1.5
31.2
5.5
27
26.67
0.7
M20
1.5
34.6
6
30
29.67
0.7
M22
1.5
36.9
6
32
31.61
0.7
M24
1.5
41.6
7
36
35.61
0.7