ASME B18.5 Round Head Short Square Neck Bolts

                                                                                         

Nominal Size	Body Dia., E		Head Dia., A		Head Height, H		Square Width, O		Squre Depth, P		Cor. Rad. on Sq., Q	Fillet Rad., R
	Max	Min	Max	Min	Max	Min	Max	Min	Max	Min	Max	Max
ASME B18.5 - 1⁄4	0.26	0.213	0.594	0.563	0.145	0.125	0.26	0.245	0.124	0.093	0.031	0.031
ASME B18.5 - 5⁄16	0.324	0.272	0.719	0.688	0.176	0.156	0.324	0.307	0.124	0.093	0.031	0.031
ASME B18.5 - 3⁄8	0.388	0.329	0.844	0.782	0.208	0.188	0.388	0.368	0.156	0.125	0.047	0.031
ASME B18.5 - 7⁄16	0.452	0.385	0.969	0.907	0.239	0.219	0.452	0.431	0.156	0.125	0.047	0.031
ASME B18.5 - 1⁄2	0.515	0.444	1.094	1.032	0.27	0.25	0.515	0.492	0.156	0.125	0.047	0.031
ASME B18.5 - 5⁄8	0.642	0.559	1.344	1.219	0.344	0.313	0.642	0.616	0.218	0.187	0.078	0.062
ASME B18.5 - 3⁄4	0.768	0.678	1.594	1.469	0.406	0.375	0.768	0.741	0.218	0.187	0.078	0.062
All dimensions are given in inches. Threads are Unified Standard, Class 2A, UNC Series, in accordance with ANSI B1.1. For thread with additive finish, the maximum diameters of Class 2A apply before plating or coating, whereas the basic diameters (Class 2A maximum diameters plus the allowance) apply to a bolt after plating or coating. Bolts are designated in the sequence shown: nominal size (number, fraction or decimal equivalent); threads per inch; nominal length (fraction or decimal equivalent); product name; material; and protective finish, if required. For example, 1⁄2-13 × 3 Round Head Short Square Neck Bolt, Steel. 375-16 × 2.50 Round Head Short Square Neck Bolt, Steel, Zinc Plated