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Flat Socket Cap Screw

ASTM F835 Flat Socket head cap screws have a countersunk head with a flat top surface and hexagonal recess. The ASTM F835 specification covers the requirements for quenched and tempered alloy steel hexagon flat countersunk head cap screws, having material properties for high-strength requirements. Dimensional specifications are governed by ASME B18.3. Flat socket head cap screws are commonly used in applications in which it is necessary to recess the head of the fastener flush with the surface.

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Dimensional Specifications

Dimensional Specifications

Dimensional SpecificationsAlloy Steel Flat Socket Cap Screw

Alloy Steel Flat Socket cap screw dimensions

Per ASME B18.3-2012
Size	Nominal	UNC	UNF	D		A		G		P		H	J		T	L
				Body		Head Diameter		Protrusion Gage Diameter		Protrusion		Head Height	Hex Socket Size		Key Engagement	Thread Length
				Max	Min	Max	Min	Max	Min	Max	Min		Fraction	Decimal	Min	Min	Max
#0	0.0600		80	0.0600	0.0568	0.1380	0.1170	0.0780	0.0770	0.0360	0.0260	0.0440	….	0.0350	0.0250	0.5000	0.6200
#1	0.0730	64	72	0.0730	0.0695	0.1680	0.1430	0.1010	0.1000	0.0400	0.0280	0.0540	….	0.0500	0.0310	0.6200	0.7700
#2	0.0860	56	64	0.0860	0.0822	0.1970	0.1630	0.1240	0.1230	0.0430	0.0310	0.0640	….	0.0500	0.0380	0.6200	0.8000
#3	0.0990	48	56	0.0990	0.0949	0.2260	0.1930	0.1480	0.1470	0.0460	0.0330	0.0730	1/16	0.0620	0.0440	0.6200	0.8300
#4	0.1120	40	48	0.1120	0.1075	0.2550	0.2180	0.1720	0.1710	0.0490	0.0360	0.0890	1/16	0.0620	0.0550	0.7500	0.9900
#5	0.1250	40	44	0.1250	0.1202	0.2810	0.2400	0.1960	0.1950	0.0510	0.0370	0.0900	5/64	0.0780	0.0610	0.7500	1.0000
#6	0.1380	32	40	0.1380	0.1329	0.3070	0.2630	0.2200	0.2190	0.0520	0.0370	0.0970	5/64	0.0780	0.0660	0.7500	1.0500
#8	0.1640	32	36	0.1640	0.1585	0.3590	0.3110	0.2670	0.2660	0.0550	0.0390	0.1120	3/32	0.0940	0.0760	0.8750	1.1900
#10	0.1900	24	32	0.1900	0.1840	0.4110	0.3590	0.3130	0.3120	0.0580	0.0410	0.1270	1/8	0.1250	0.0870	0.8750	1.2700
#12	0.2120	24	28	0.2160	0.2095	0.4500	0.4100	0.3600	0.3590	0.0690	0.0420	0.1350	1/8	0.1250	0.0940	1.0000	1.3300
1/4	0.2500	20	28	0.2500	0.2435	0.5310	0.4800	0.4240	0.4230	0.0640	0.0430	0.1610	5/32	0.1560	0.1110	1.0000	1.5000
5/16	0.3125	18	24	0.3125	0.3053	0.6560	0.6000	0.5390	0.5380	0.0700	0.4700	0.1980	3/16	0.1880	0.1350	1.1250	1.7100
3/8	0.3750	16	24	0.3750	0.3678	0.7810	0.7200	0.6530	0.6520	0.0760	0.0500	0.2340	7/32	0.2190	0.1590	1.2500	1.9400
7/16	0.4375	14	20	0.4375	0.4294	0.8440	0.7810	0.6900	0.6890	0.0920	0.0630	0.2340	1/4	0.2500	0.1590	1.3750	2.1700
1/2	0.5000	13	20	0.5000	0.4919	0.9380	0.8720	0.7390	0.7380	0.1190	0.0870	0.2510	5/16	0.3120	0.1720	1.5000	2.3800
5/8	0.6250	11	18	0.6250	0.6163	1.1880	1.1120	0.9620	0.9610	0.1350	0.0960	0.3240	3/8	0.3750	0.2200	1.7500	2.8200
3/4	0.7500	10	16	0.7500	0.7406	1.4380	1.3550	1.1860	1.1850	0.1500	0.1050	0.9600	1/2	0.5000	0.2200	2.0000	3.2500
7/8	0.8750	9	14	0.8750	0.8647	1.6880	1.6040	1.4110	1.1410	0.1650	0.1180	0.4680	9/16	0.5620	0.2480	2.2500	3.6900
1	1.0000	8	14	1.0000	0.9886	1.9380	1.8410	1.6350	1.6340	0.1810	0.1300	0.5400	5/8	0.6250	0.2970	2.5000	4.1200
1 1/8	1.1250	7	12	1.1250	1.1086	2.1880	2.0790	1.8590	1.8580	0.1960	0.1400	0.6110	3/4	0.7500	0.3250	2.8100	4.6500
1 1/4	1.2500	7	12	1.2500	1.2336	2.4380	2.3160	2.0830	2.0820	0.2120	0.1500	0.6830	7/8	0.8750	0.3580	3.1200	5.0900
1 3/8	1.3750	7	12	1.3750	1.3568	2.6880	2.5530	2.3060	2.3050	0.2280	0.1620	0.7550	7/8	0.8750	0.4020	3.4400	5.6500
1 1/2	1.5000	6	12	1.5000	1.4818	2.9380	2.7910	2.5300	2.5290	0.2430	0.1730	0.8270	1	1.0000	0.4350	3.7500	6.0800

All dimensions are in inches.

Flat Socket Cap Screw

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1/4

1/2

SFLA0250050

In Stock

$0.12925/EA

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1/4-20 X 1/2 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$0.12925/EA

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In Stock

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Quantity	Price
Quantity	Price
1	$0.12925/EA
1220	$0.12251/EA
4880	$0.11135/EA
21960	$0.07577/EA

1/4

5/8

SFLA0250062

In Stock

$0.13125/EA

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1/4-20 X 5/8 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$0.13125/EA

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In Stock

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Quantity	Price
Quantity	Price
1	$0.13125/EA
1070	$0.12441/EA
4260	$0.11308/EA
19150	$0.07695/EA

1/4

3/4

SFLA0250075

In Stock

$0.0975/EA

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1/4-20 X 3/4 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$0.0975/EA

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In Stock

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Quantity	Price
Quantity	Price
1	$0.0975/EA
940	$0.09242/EA
3740	$0.084/EA
16830	$0.05716/EA

1/4

SFLA0250100

In Stock

$0.17661/EA

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1/4-20 X 1 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$0.17661/EA

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In Stock

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Quantity	Price
Quantity	Price
1	$0.17661/EA
750	$0.1674/EA
2990	$0.15215/EA
13440	$0.10354/EA

1/4

1 1/4

SFLA0250125

In Stock

$0.22129/EA

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1/4-20 X 1 1/4 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$0.22129/EA

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In Stock

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Quantity	Price
Quantity	Price
1	$0.22129/EA
630	$0.20975/EA
2520	$0.19065/EA
11330	$0.12973/EA

1/4

1 1/2

SFLA0250150

In Stock

$0.30321/EA

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1/4-20 X 1 1/2 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$0.30321/EA

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In Stock

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Quantity	Price
Quantity	Price
1	$0.30321/EA
550	$0.28741/EA
2180	$0.26123/EA
9790	$0.17776/EA

1/4

SFLA0250200

In Stock

$0.34532/EA

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1/4-20 X 2 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$0.34532/EA

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In Stock

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Quantity	Price
Quantity	Price
1	$0.34532/EA
400	$0.32732/EA
1580	$0.29751/EA
7090	$0.20245/EA

1/4

2 1/2

SFLA0250250

In Stock

$0.48811/EA

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1/4-20 X 2 1/2 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$0.48811/EA

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In Stock

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Quantity	Price
Quantity	Price
1	$0.48811/EA
320	$0.46266/EA
1260	$0.42052/EA
5650	$0.28616/EA

5/8

1 1/4

SFLA0620125

Out Of Stock

$0.92857/EA

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5/8-11 X 1 1/4 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$0.92857/EA

Qty

Out Of Stock

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Quantity	Price
Quantity	Price
1	$0.92857/EA
100	$0.88016/EA
370	$0.8/EA
1640	$0.54439/EA

5/8

1 1/2

SFLA0620150

In Stock

$1.58614/EA

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5/8-11 X 1 1/2 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$1.58614/EA

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In Stock

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Quantity	Price
Quantity	Price
1	$1.58614/EA
80	$1.50345/EA
310	$1.36652/EA
1380	$0.9299/EA

5/8

1 3/4

SFLA0620175

In Stock

$3.27011/EA

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5/8-11 X 1 3/4 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$3.27011/EA

Qty

In Stock

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Quantity	Price
Quantity	Price
1	$3.27011/EA
70	$3.09963/EA
270	$2.81732/EA
1210	$1.91715/EA

5/8

SFLA0620200

In Stock

$1.20807/EA

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5/8-11 X 2 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$1.20807/EA

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In Stock

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Quantity	Price
Quantity	Price
1	$1.20807/EA
60	$1.14509/EA
240	$1.0408/EA
1080	$0.70825/EA

5/8

2 1/2

SFLA0620250

In Stock

$3.07857/EA

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5/8-11 X 2 1/2 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$3.07857/EA

Qty

In Stock

Product Detail

Quantity	Price
Quantity	Price
1	$3.07857/EA
50	$2.91808/EA
200	$2.65231/EA
890	$1.80486/EA

5/8

SFLA0620300

In Stock

$2.19368/EA

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5/8-11 X 3 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$2.19368/EA

Qty

In Stock

Product Detail

Quantity	Price
Quantity	Price
1	$2.19368/EA
50	$2.07932/EA
180	$1.88994/EA
780	$1.28608/EA

5/8

3 1/2

SFLA0620350

In Stock

$3.00536/EA

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5/8-11 X 3 1/2 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$3.00536/EA

Qty

In Stock

Product Detail

Quantity	Price
Quantity	Price
1	$3.00536/EA
40	$2.84868/EA
150	$2.58923/EA
640	$1.76193/EA

5/8

SFLA0620400

In Stock

$3.14643/EA

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5/8-11 X 4 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$3.14643/EA

Qty

In Stock

Product Detail

Quantity	Price
Quantity	Price
1	$3.14643/EA
30	$2.9824/EA
120	$2.71077/EA
540	$1.84464/EA

5/8

4 1/2

SFLA0620450

In Stock

$9.35714/EA

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5/8-11 X 4 1/2 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$9.35714/EA

Qty

In Stock

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Quantity	Price
Quantity	Price
1	$9.35714/EA
30	$8.86933/EA
110	$8.06154/EA
500	$5.48576/EA

5/8

5 1/2

SFLA0620550

In Stock

$19.56546/EA

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5/8-11 X 5 1/2 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$19.56546/EA

Qty

In Stock

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Quantity	Price
Quantity	Price
1	$19.56546/EA
25	$18.54546/EA
90	$16.8564/EA
500	$11.47054/EA

5/8

SFLA0620600

In Stock

$4.37661/EA

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5/8-11 X 6 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$4.37661/EA

Qty

In Stock

Product Detail

Quantity	Price
Quantity	Price
1	$4.37661/EA
25	$4.14844/EA
90	$3.77062/EA
500	$2.56585/EA

5/8

6 1/2

SFLA0620650

In Stock

$22.21814/EA

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5/8-11 X 6 1/2 F835 ALLOY STEEL FLAT SOCKET CAP SCREW

$22.21814/EA

Qty

In Stock

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Quantity	Price
Quantity	Price
1	$22.21814/EA
25	$21.05985/EA
80	$19.14178/EA
500	$13.02571/EA

ASTM F835	This specification covers the requirements for quenched and tempered alloy steel hexagon socket button (SBHCS) 0.060 through 0.625 thread sizes and flat countersunk (SFHCS) 0.060 through 1.5 thread sizes head cap screws having material properties for high-strength requirements.
ASME B18.3	Covers the complete general and dimensional data for various types of hexagon socket cap screws, shoulder screws, set screws, and hexagon keys recognized as an American National Standard.
ASME B1.1 UNC & UNF Class 2A	Specifies the thread form, series, class, allowance, tolerance, and designation for unified screw threads.

Quenched & Tempered Alloy Steel		Per ASTM F835-16
Nominal Diameter	Full-Size Screws	Machined Test Specimen				Product Hardness
	Tensile Strength	Yield Strength at 0.2% offset	Tensile Strength	Elongation in 4D	Reduction of Area	Rockwell C	Vickers DPH
	ksi	ksi	ksi	%	%	Rockwell C	Vickers DPH
1/2" & under	145 min	(1)	(1)	(1)	(1)	39-44	382-434
over 1/2"	135 min	153 min	170 min	8 min	35 min	37-44	363-434

Per ASTM F835-16
Material	Heat Analysis				Product Analysis
	Carbon	Phosphorus	Sulfur	Alloying Elements	Carbon	Phosphorus	Sulfur	Alloying Elements
	% by weight	% by weight	% by weight	Alloying Elements	% by weight	% by weight	% by weight	Alloying Elements
Quenched and tempered alloy steel	0.30 to 0.48	0.035 max	0.040 max	(1)	0.28 to 0.50	0.040 max	0.045 max	(1)