材质 
M12
1.75
20.88
8
0.6
19
13
M16
2
26.17
10
0.6
24
17
M20
2.5
32.95
13
0.8
30
21
M22
2.5
35.03
14
0.8
32
23
M24
3
39.55
15
0.8
36
25
M27
3
45.2
17
1
41
28
M30
3.5
50.85
19
1
46
31