Technical Info

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Nominal Size or Basic Major Thread Diameter		Width Across Flats			Width Across Corners		Thickness
Nominal Size or Basic Major Thread Diameter		Basic	Max	Min	Max	Min	Basic	Max	Min
1/4	0.25	7/16	0.438	0.428	0.505	0.488	7/32	0.226	0.212
5/16	0.3125	1/2	0.5	0.489	0.577	0.557	17/64	0.273	0.258
3/8	0.375	9/16	0.562	0.551	0.65	0.628	21/64	0.337	0.32
7/16	0.4375	11/16	0.688	0.675	0.794	0.768	3/8	0.385	0.365
1/2	0.5	3/4	0.75	0.736	0.866	0.84	7/16	0.448	0.427
9/16	0.5625	7/8	0.875	0.861	1.01	0.982	31/64	0.496	0.473
5/8	0.625	15/16	0.938	0.922	1.083	1.051	35/64	0.559	0.535
3/4	0.75	1-1/8	1.125	1.088	1.299	1.24	41/64	0.665	0.617
7/8	0.875	1-5/16	1.312	1.269	1.516	1.447	3/4	0.776	0.724
1	1	1-1/2	1.5	1.45	1.732	1.653	55/64	0.887	0.831
1-1/8	1.125	1-11/16	1.688	1.631	1.949	1.859	31/32	0.999	0.939
1-3/8	1.375	2-1/16	2.062	1.994	2.382	2.273	1-11/64	1.206	1.138
1-1/2	1.5	2-1/4	2.25	2.175	2.598	2.48	1-9/32	1.317	1.245
1-5/8	1.625	2-7/16	2.438	2.356	2.815	2.686	1-25/64	1.429	1.353
1-3/4	1.75	2-5/8	2.625	2.538	3.031	2.893	1-1/2	1.54	1.46
2	2	3	3	2.9	3.464	3.306	1-23/32	1.763	1.675
2-1/4	2.25	3-3/8	3.375	3.263	3.897	3.719	1-15/16	1.986	1.89
2-1/2	2.5	3-3/4	3.75	3.625	4.33	4.133	2-5/32	2.209	2.105
2-3/4	2.75	4-1/8	4.125	3.988	4.763	4.546	2-3/8	2.431	2.319