Plain Washers, Black : Metric Series
(Dimensions in Millimetres)
Designation Internal Diameter External Diameter Thickness
(Thread d1 d2 s
Diameter) Max Min Max Min 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 29.0 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
M56 63.0 62.0 92.0 90.0 9.2 6.8
(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
Non-preferred sizes in brackets().