Single Coil Square Section Spring Washers : Metric Series, Type A
(Dimensions in milimetres)
Nominal Size Inside Diameter Thickness Outside
and Thread d1 and Diameter Radius
Diameter Width d2 r
d max min s max max
M3 3.3 3.1 1+0.1 5.5 0.3
(M3.5) 3.8 3.6 1+0.1 6.0 0.3
M4 4.35 4.1 1.2+0.1 6.95 0.4
M5 5.35 5.1 1.5+0.1 8.55 0.5
M6 6.4 6.1 1.5+0.1 9.6 0.5
M8 8.55 8.2 2+0.1 12.75 0.65
M10 10.6 10.2 2.5+0.15 15.9 0.8
M12 12.6 12.2 2.5+0.15 17.9 0.8
(M14) 14.7 14.2 3+0.2 21.1 1.0
M16 16.9 16.3 3.5+0.2 24.3 1.15
(M18) 19.0 18.3 3.5+0.2 26.4 1.15
M20 21.1 20.3 4.5+0.2 30.5 1.5
(M22) 23.3 22.4 4.5+0.2 32.7 1.5
M24 25.3 24.4 5+0.2 35.7 1.65
M27 28.5 27.5 5+0.2 38.9 1.65
M30 31.5 30.5 6+0.2 43.9 2.0
(M33) 34.6 33.5 6+0.2 43.9 2.0
M36 37.6 36.5 7+0.25 52.1 2.3
(M39) 40.8 39.6 7+0.25 55.3 2.3
M42 43.8 42.6 8+0.25 60.3 2.65
(M45) 46.8 45.6 8+0.25 63.3 2.65
M48 50.0 48.8 8+0.25 66.5 2.65
Sizes shown in brackets are non-perferred and are not usually stock sizes.