材质 
M12
1.75
22.78
10.8
10.37
21
20.16
M16
2
29.56
14.8
14.1
27
26.16
M20
2.5
37.29
18
16.9
34
33
M22
2.5
39.55
19.4
18.1
36
35
M24
3
45.2
21.5
20.2
41
40
M27
3
50.85
23.8
22.5
46
45
M30
3.5
55.37
25.6
24.3
50
49
M36
4
66.44
31
29.4
60
58.8