Related Resources: hardware

BS 4320 Black Metric Washer

Engineering ANSI Hardware Design Data
Engineering Metric Hardware Design Data

BS 4320 Plain Washer, Black Metric Series

ISO BS EN DIN 4320 Plain Washer, Bright Metric Series

All dimensions in mm.

Designation
(thread diameter)a
Internal
diameter
d1
External
diameter
d2
Thickness s
max.
min.
max.
min.
Thick
(normal)
max.
min.
M5
5.8
5.5
10.0
9.2
1.2
0.8
M6
7.0
6.6
12.5
11.7
1.9
1.3
(M7)
8.0
7.6
14.0
13.2
1.9
1.3
M8
9.4
9.0
17.0
16.2
1.9
1.3
M10
11.5
11.0
21.0
20.2
2.3
1.7
M12
14.5
14.0
24.0
23.2
2.8
2.2
(M14)
16.5
16.0
28.0
27.2
2.8
2.2
M16
18.5
18.0
30.0
29.2
3.6
2.4
(M18)
20.6
20.0
34.0
32.8
3.6
2.4
M20
22.6
22.0
37.0
35.8
3.6
2.4
(M22)
24.6
24.0
39.0
37.8
3.6
2.4
M24
26.6
26.0
44.0
42.8
4.6
3.4
(M27)
30.6
30.0
50.0
48.8
4.6
3.4
M30
33.8
33.0
56.0
54.5
4.6
3.4
(M33)
36.8
36.0
60.0
58.5
6.0
4.0
M36
39.8
39.0
66.0
64.5
6.0
4.0
(M39)
42.8
42.0
72.0
70.5
7.0
5.0
M42
45.8
45.0
78.0
76.5
8.2
5.8
(M45)
48.8
48.0
85.0
83.0
8.2
5.8
M48
53.0
52.0
92.0
90.0
9.2
6.8
(M52)
57.0
56.0
98.0
96.0
9.2
6.8
M56
63.0
62.0
105.0
103.0
10.2
7.8
(M60)
67.0
66.0
110.0
108.0
10.2
7.8
M64
71.0
70.0
115.0
113.0
10.2
7.8
(M68)
75.0
74.0
120.0
118.0
11.2
8.8