材质 
M12
1.75
20.03
18
17.73
12
11.57
M14
2
23.35
21
20.67
14.1
13.4
M16
2
26.75
24
23.67
16.4
15.7
M18
2.5
29.56
27
26.16
17.6
16.9
M20
2.5
32.95
30
29.16
20.3
19
M22
2.5
37.29
34
33
21.8
20.5
M24
3
39.55
36
35
23.9
22.6
M27
3
45.2
41
40
26.7
25.4
M30
3.5
50.85
46
45
28.6
27.3
M33
3.5
55.37
50
49
32.5
30.9
M36
4
60.79
55
53.8
34.7
33.1
M39
4
66.44
60
58.8
37.5
35.9
M42
4.5
72.02
65
63.8
40.3
38.7