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510-638 — BACK HEAD CAP SCREW

✓ Government record, cited
— · BOLT SCREW
PRODUCT OVERVIEW

510-638: BACK HEAD CAP SCREW.

The BACK HEAD CAP SCREW is a the manufacturer industrial component. Key specifications include head_style: FILLISTER, head_height: 0.053 INCHES MINIMUM AND 0.062 INCHES MAXIMUM IN, thread_class: 2A A, head_diameter: 0.135 INCHES MINIMUM AND 0.145 INCHES MAXIMUM IN, thread_length: 0.269 INCHES MINIMUM AND 0.320 INCHES MAXIMUM IN, screw_material: STEEL CORROSION RESISTING. This part is cataloged in the U.S.

Government catalog under NSN 5305-00-108-9943, indicating validated use in U.S. government and defense logistics supply chains. Available through authorized enterprise resellers and TPM (Third Party Maintenance) channels.

Verify compatibility with your specific system configuration before ordering.

WHERE IT FITS
510-638
NSN: 5305-00-108-9943
NIINs: 001089943, 010484810
FSC: 5305 — Screws
CAGE: 18937 — S-TECH, INC. (USA)
SPECIFICATIONS
head_styleFILLISTER
head_height0.053 INCHES MINIMUM AND 0.062 INCHES MAXIMUM IN
thread_class2A A
head_diameter0.135 INCHES MINIMUM AND 0.145 INCHES MAXIMUM IN
thread_length0.269 INCHES MINIMUM AND 0.320 INCHES MAXIMUM IN
screw_materialSTEEL CORROSION RESISTING
fastener_length0.300 INCHES MINIMUM AND 0.320 INCHES MAXIMUM IN
thread_directionRIGHT-HAND
internal_drive_styleSLOT
nominal_thread_diameter0.086 INCHES IN
thread_quantity_per_inch64
thread_series_designatorUNF
NSN5305-00-108-9943
COMPONENT DIAGRAM
BOLT / SCREW — THREAD VERIFICATION REQUIRED Hex HEAD LENGTH: — THREAD: — × — MATERIAL: — PN: 510-638 · OEM ⚠ VERIFY BEFORE ORDERING Verify thread pitch before ordering — metric (M8×1.25) ≠ imperial (5/16-18). Wrong thread = wrong part. Grade/class stamped on bolt head determines tensile strength ✓ BROKER TIP Grade/class stamped on head determines tensile strength. Grade 8 > Grade 5 > Grade 2. Always confirm head marking matches specification requirement PARTSTABLE TECHNICAL DRAWING — NOT TO SCALE
KEY FEATURES
•
HEAD HEIGHT: 0.053 INCHES MINIMUM AND 0.062 INCHES MAXIMUM IN
•
FASTENER LENGTH: 0.300 INCHES MINIMUM AND 0.320 INCHES MAXIMUM IN
•
THREAD LENGTH: 0.269 INCHES MINIMUM AND 0.320 INCHES MAXIMUM IN
•
NOMINAL THREAD DIAMETER: 0.086 INCHES IN
•
HEAD STYLE: FILLISTER
•
THREAD DIRECTION: RIGHT-HAND
•
SCREW MATERIAL: STEEL CORROSION RESISTING
•
INTERNAL DRIVE STYLE: SLOT
TECHNICAL CHARACTERISTICS
HEAD HEIGHT0.053 INCHES MINIMUM AND 0.062 INCHES MAXIMUM IN
FASTENER LENGTH0.300 INCHES MINIMUM AND 0.320 INCHES MAXIMUM IN
THREAD LENGTH0.269 INCHES MINIMUM AND 0.320 INCHES MAXIMUM IN
NOMINAL THREAD DIAMETER0.086 INCHES IN
HEAD STYLEFILLISTER
THREAD DIRECTIONRIGHT-HAND
SCREW MATERIALSTEEL CORROSION RESISTING
INTERNAL DRIVE STYLESLOT
THREAD CLASS2A A
THREAD QUANTITY PER INCH64
SUBSTITUTES & CROSS-REFERENCES

No substitute or cross-reference records for this part.

LIFECYCLE
NSN statusActive· U.S. Government catalog
Acquisition advice: Normally procured from the manufacturer (OEM)No demilitarization required
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FREQUENTLY ASKED QUESTIONS
What is 510-638?
510-638 is a BACK HEAD CAP SCREW.
What is the NSN for 510-638?
510-638 is cataloged in the U.S. Government catalog under NSN 5305-00-108-9943. This indicates validated use in U.S. government and defense supply chains.
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✓ PartsTable — the parts reference. Every fact cited to its source.
PartsTable Design LLC · partstable.com
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.
PartsTable commercial catalog: edition Unified commercial catalog snapshot through 2026-09-28, edition date not on file, retrieved 2026-09-28.