ASME B18.16.6 Dimensions of Prevailing Torque All-Metal Type Hex Nuts

Designation	Nominal Diameter	Width Across Flats, A		Width Across Corners, B		Thickness, C		Minimum Hex Height, D	Maximum Runout of Bearing Surface With Thread P.D. FIM
Designation	Nominal Diameter	Max.	Min.	Max.	Min.	Max.	Min.	Minimum Hex Height, D	Maximum Runout of Bearing Surface With Thread P.D. FIM
#4	0.1120	0.251	0.241	0.289	0.275	0.163	0.087	0.066	0.008
#6	0.1380	0.313	0.302	0.361	0.344	0.171	0.102	0.075	0.008
#8	0.1640	0.345	0.332	0.397	0.378	0.191	0.117	0.083	0.009
#10	0.1900	0.376	0.362	0.433	0.413	0.241	0.117	0.083	0.009
#12	0.2160	0.438	0.423	0.505	0.482	0.241	0.148	0.103	0.010
¼	0.2500	0.4385	0.428	0.505	0.488	0.288	0.212	0.145	0.010
5⁄16	0.3125	0.5020	0.489	0.577	0.557	0.336	0.258	0.166	0.011
⅜	0.3750	0.5645	0.551	0.650	0.628	0.415	0.320	0.198	0.012
7⁄16	0.4375	0.6895	0.675	0.794	0.768	0.463	0.365	0.223	0.013
½	0.5000	0.7520	0.736	0.866	0.840	0.573	0.427	0.262	0.014
9⁄16	0.5625	0.8770	0.861	1.010	0.982	0.621	0.473	0.286	0.015
⅝	0.6250	0.9395	0.922	1.083	1.051	0.731	0.535	0.329	0.016
¾	0.7500	1.1270	1.088	1.299	1.240	0.827	0.617	0.382	0.018
⅞	0.8750	1.3145	1.269	1.516	1.447	0.922	0.724	0.450	0.020
1	1.0000	1.5020	1.450	1.732	1.653	1.018	0.831	0.513	0.022
1¹/₈	1.1250	1.6895	1.631	1.949	1.859	1.176	0.939	0.576	0.025
1¼	1.2500	1.8770	1.812	2.165	2.066	1.272	1.030	0.628	0.028
1⅜	1.3750	2.0645	1.994	2.382	2.273	1.399	1.138	0.681	0.031
1½	1.5000	2.2520	2.175	2.598	2.480	1.526	1.245	0.757	0.034