Imperial Button Head Socket

*Button Head Sockets

Unified National Coarse / Fine

S350 - UNC/UNF Bare Steel

ANSI/ASME B18.3

1986

Button Head Socket Technical Drawing
Coarse Thread Fine Thread
Coarse Thread
Diameter d #6-32 #8-32 #10-24 1/4-20 5/16-18 3/8-16 1/2-13 5/8-11
Diameter Code 006 008 010 014 016 018 024 026
t min. .044 .052 .070 .087 .105 .122 .175 .210
s 5/64 3/32 1/8 5/32 3/16 7/32 5/16 3/8
.078 .094 .125 .156 .188 .219 .312 .375
k max. .073 .087 .101 .132 .166 .199 .265 .331
d1 max. .262 .312 .361 .437 .547 .656 .875 1.000
Length Code Pkg.
Order Number -> 1/4 x 2-1/2 = S350-014-0250 (Diameter Code x Length Code)
1/8 0013 100        
3/16 0019 100        
1/4 0025 100 100 100      
3/8 0038 100 100 100 100 100 100   
1/2 0050 100 100 100 100 100 100   
5/8 0063 100 100 100 100 100 100 100  
3/4 0075 100 100 100 100 100 100 100  
7/8 0088    100  100 100  
1 0100 100 100 100 100 100 100 100 50
1-1/4 0125   100 100 100 100 100 50
1-1/2 0150  100 100 100 100 50 100 50
1-34 0175    100     
2 0200   100 100 100 50 50 50
2-1/2 0250    100    50
3 0300    100     

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Fine Thread
Diameter d #10-32 1/4-28 5/16-24 3/8-24
Diameter Code 010 014 016 018
t min. .070 .087 .105 .122
s 1/8 5/32 3/16 7/32
.125 .156 .188 .219
k max. .101 .132 .166 .199
d1 max. .361 .437 .547 .656
Length Code Pkg.
Order Number -> 1/4 x 1 = S350-014-0100 (Diameter Code x Length Code)(Fine Thread add -F)
1/4 0025 100    
3/8 0038 100    
1/2 0050 100 100   
5/8 0063 100 100   
3/4 0075 100 100 100 100
1 0100 100 100  100
1-1/2 0150 100    
*NOTE
This product is designed and recommended for light fastening applications such as guards, hinges, etc. It is not suggested for use in critical high strength applications where socket head cap screws should normally be used.

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