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903-5912051PC21 — SCREW,CAP,SOCKET HEAD

✓ Government record, cited
— · BOLT SCREW
PRODUCT OVERVIEW

903-5912051PC21: SCREW,CAP,SOCKET HEAD.

The SCREW,CAP,SOCKET HEAD is a the manufacturer industrial component. Key specifications include material: STEEL OVERALL, thread_class: 2A A, fastener_length: 2.000 INCHES NOMINAL IN, internal_drive_style: HEXAGON, nominal_thread_diameter: 0.312 INCHES IN, thread_quantity_per_inch: 18. This part is cataloged in the U.S.

Government catalog under NSN 5305-01-417-4644, 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
903-5912051PC21
NSN: 5305-01-417-4644
FSC: 5305 — Screws
CAGE: 53711 — NAVAL SEA SYSTEMS COMMAND (USA)
SPECIFICATIONS
materialSTEEL OVERALL
thread_class2A A
fastener_length2.000 INCHES NOMINAL IN
internal_drive_styleHEXAGON
nominal_thread_diameter0.312 INCHES IN
thread_quantity_per_inch18
thread_series_designatorUNIFIED NATIONAL COARSE (UNC)
NSN5305-01-417-4644
COMPONENT DIAGRAM
BOLT / SCREW — THREAD VERIFICATION REQUIRED Hex HEAD LENGTH: — THREAD: — × — MATERIAL: — PN: 903-5912051PC21 · 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
•
FASTENER LENGTH: 2.000 INCHES NOMINAL IN
•
NOMINAL THREAD DIAMETER: 0.312 INCHES IN
•
INTERNAL DRIVE STYLE: HEXAGON
•
THREAD CLASS: 2A A
•
THREAD QUANTITY PER INCH: 18
•
MATERIAL: STEEL OVERALL
•
THREAD SERIES DESIGNATOR: UNIFIED NATIONAL COARSE (UNC)
TECHNICAL CHARACTERISTICS
FASTENER LENGTH2.000 INCHES NOMINAL IN
NOMINAL THREAD DIAMETER0.312 INCHES IN
INTERNAL DRIVE STYLEHEXAGON
THREAD CLASS2A A
THREAD QUANTITY PER INCH18
MATERIALSTEEL OVERALL
THREAD SERIES DESIGNATORUNIFIED NATIONAL COARSE (UNC)
SUBSTITUTES & CROSS-REFERENCES 1
ANSI B18.3Reference document
Same NSN cross-reference
Reference document — Secondary reference
LIFECYCLE
NSN statusActive· U.S. Government catalog
Acquisition advice: Insurance item — stocked against contingency demandNo demilitarization required
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FREQUENTLY ASKED QUESTIONS
What is 903-5912051PC21?
903-5912051PC21 is a SCREW,CAP,SOCKET HEAD.
What parts can replace 903-5912051PC21?
There is 1 known substitute for 903-5912051PC21: ANSI B18.3. Substitute compatibility should be verified for your specific system.
What is the NSN for 903-5912051PC21?
903-5912051PC21 is cataloged in the U.S. Government catalog under NSN 5305-01-417-4644. 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.