Technical Info

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SAE Flat Washer Dimensions Per ASME B18.21.1

Size	Inside Diameter (ID)			Outside Diameter (OD)			Thickness (TH)
	Tolerance			Tolerance			Thickness (TH)
	Basic	Plus	Minus	Basic	Plus	Minus	Max	Min
#4	0.125	0.008	0.005	0.312	0.008	0.005	0.040	0.025
#6	0.156	0.008	0.005	0.375	0.015	0.005	0.065	0.036
#8	0.188	0.008	0.005	0.438	0.015	0.005	0.065	0.036
#10	0.219	0.008	0.005	0.500	0.015	0.005	0.065	0.036
#12	0.250	0.015	0.005	0.562	0.015	0.005	0.080	0.051
1/4	0.281	0.015	0.005	0.625	0.015	0.005	0.080	0.051
5/16	0.344	0.015	0.005	0.688	0.015	0.007	0.080	0.051
3/8	0.406	0.015	0.005	0.812	0.015	0.007	0.080	0.051
7/16	0.469	0.015	0.005	0.922	0.015	0.007	0.080	0.051
1/2	0.531	0.015	0.005	1.062	0.030	0.007	0.121	0.074
9/16	0.594	0.015	0.005	1.156	0.030	0.007	0.121	0.074
5/8	0.656	0.030	0.007	1.312	0.030	0.007	0.121	0.074
3/4	0.812	0.030	0.007	1.469	0.030	0.007	0.160	0.108
7/8	0.938	0.030	0.007	1.750	0.030	0.007	0.160	0.108
1	1.062	0.030	0.007	2.000	0.030	0.007	0.160	0.108
1 1/8	1.250	0.030	0.007	2.250	0.030	0.007	0.160	0.108
1 1/4	1.375	0.030	0.007	2.500	0.030	0.007	0.192	0.136
1 3/8	1.500	0.030	0.007	2.750	0.030	0.007	0.192	0.136
1 1/2	1.625	0.030	0.007	3.000	0.030	0.007	0.192	0.136
1 3/4	1.875	0.045	0.010	3.375	0.045	0.010	0.213	0.153
2	2.125	0.045	0.010	3.750	0.045	0.010	0.213	0.153