BS 450 Round Head Screws

Nom. Size of Screw	Basic Dia. D	Threads per Inch		Dia. of Head A		Depth of Head B		Width of Slot H		Depth of Slot J
Nom. Size of Screw	Basic Dia. D	BSW	BSF	Max.	Min.	Max.	Min.	Max.	Min.	Depth of Slot J
BS 450 - 1⁄8	0.125	40	...	0.219	0.206	0.087	0.082	0.039	0.032	0.048
BS 450 - 3⁄16	0.1875	24	32c	0.328	0.312 d	0.131	0.124	0.05	0.042	0.072
BS 450 - 7⁄32	0.2188	...	28c	0.383	0.365	0.153	0.145	0.055	0.046	0.084
BS 450 - 1⁄4	0.25	20	26	0.438	0.417	0.175	0.165	0.061	0.051	0.096
BS 450 - 5⁄16	0.3125	18	22	0.547	0.524	0.219	0.207	0.071	0.061	0.12
BS 450 - 3⁄8	0.375	16	20	0.656	0.629	0.262	0.249	0.082	0.072	0.144
BS 450 - 7⁄16	0.4375	14	18	0.766	0.735	0.306	0.291	0.093	0.082	0.168
BS 450 - 1⁄2	0.5	12	16	0.875	0.84	0.35	0.333	0.104	0.092	0.192
BS 450 - 9⁄16	0.5625	12c	16c	0.984	0.946	0.394	0.375	0.115	0.103	0.217
BS 450 - 5⁄8	0.625	11	14	1.094	1.051	0.437	0.417	0.126	0.113	0.24
BS 450 - 3⁄4	0.75	10	12	1.312	1.262	0.525	0.5	0.148	0.134	0.288
a All dimensions, except J, given for the 18-through 38-inch sizes also apply to all the 90° Raised Countersunk Head Screw dimensions given in the Standard. b These screws are also available with recessed heads; recess are not given here but may be found in the Standard. c Non-preferred size; avoid use whenever possible. d By arrangement may also be 0.309. e By arrangement may also be 0.468. All dimensions in inches.