材质 
M14
2
22
21.72
14.35
13.65
M16
2
24
23.72
16.35
15.65
M20
2.5
30
29.72
20.42
19.58
M24
3
36
35.66
24.42
23.58
M27
3
41
40.66
27.42
26.58
M30
3.5
46
45.66
30.5
29.5
M33
3.5
50
49.66
33.5
32.5
M36
4
55
54.6
36.5
35.5
M39
4
60
59.6
39.5
38.5
M45
4.5
70
69.6
45.5
44.5
M56
5.5
85
84.5
56.6
55.4