Imperial Socket Set Screws

Unified National Coarse / Fine

S333 - UNC/UNF Bare Steel

ANSI/ASME B18.3

1986

Coarse Thread
Diameter d		0-80	4-40	6-32	8-32	10-24	1/4-20	5/16-18	3/8-16	7/16-14	1/2-13	5/8-11	3/4-10	7/8-9
Diameter Code		000	004	006	008	010	014	016	018	020	024	026	028	030
t min.		.050	.070	.080	.090	.100	.125	.126	.188	.219	.250	.312	.454	.500
s		-	-	¹/₁₆	⁵/₆₄	³/₃₂	¹/₈	⁵/₃₂	³/₁₆	⁷/₃₂	¹/₄	⁵/₁₆	³/₈	¹/₂
s		.028	.050	.062	.078	.094	.125	.156	.188	.219	.250	.312	.375	.500
Length	Code	Pkg.
Order Number -> 1/4 x 1 = S333-014-0100 (Diameter Code x Length Code)
3/32	0009	100
1/8	0013	100	100	100
3/16	0019		100	100	100	100
1/4	0025		100	100	100	100	100	100	100
5/16	0031		100	100	100	100	100	100
3/8	0038		100	100	100	100	100	100	100
1/2	0050		100	100	100	100	100	100	100	100	100	50
5/8	0063			100	100	100	100	100	100		100	50
3/4	0075			100	100	100	100	100	100	100	100	50	50
7/8	0088						100
1	0100			100	100	100	100	100	100	100	100	50	50	25
1-1/4	0125						100	100	100		100	50
1-1/2	0150						100	100	100		100	50
2	0200							100			50		25
2-1/2	0250										50
3	0300										50

Fine Thread
Diameter d		#10-32	1/4-28	5/16-24	3/8-24	7/16-20	1/2-20	5/-18	3/4-16
Diameter Code		010	014	016	018	020	024	026	028
t min.		.100	.125	.156	.188	.219	.250	.312	.454
s		³/₃₂	¹/₈	⁵/₃₂	³/₁₆	7/32	1/4	5/16	3/8
s		.094	.125	.156	.188	.219	.250	.312	.375
Length	Code	Pkg.
Order Number -> 1/4 x 1 = S333-014-0100-F (Diameter Code x Length Code)(Fine Thread add -F)
3/16	0019	10	10
1/4	0025	100	100
5/16	0031	100	100	100	100
3/8	0038	100	100	100	100
7/16	0040
1/2	0050	100	100	100	100		100	50
5/8	0063	100			100	100	100
3/4	0075	100	100	100	100			50
1	0100	100	100	100	100				50