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A51K5611-5 — PACKING NUT

✓ Government record, cited
— · HOSE FITTING
PRODUCT OVERVIEW

A51K5611-5: PACKING NUT.

The PACKING NUT is a the manufacturer industrial component. Key specifications include material: STEEL, thread_size: 3-16, thread_class: 3B, thread_length: 0.540 INCHES NOMINAL IN, overall_length: 1.490 INCHES NOMINAL IN, style_designator: KNURLED, INTERNAL THREAD, SHOULDERED. This part is cataloged in the U.S.

Government catalog under NSN 4730-01-356-1040, 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
A51K5611-5
NSN: 4730-01-356-1040
FSC: 4730 — Hose, Pipe, Tube, Lubrication, and Railing Fittings
CAGE: 9J659 — D F P MANUFACTURING CORP DBA D F P (USA)
SPECIFICATIONS
materialSTEEL
thread_size3-16
thread_class3B
thread_length0.540 INCHES NOMINAL IN
overall_length1.490 INCHES NOMINAL IN
style_designatorKNURLED, INTERNAL THREAD, SHOULDERED
thread_directionRIGHT-HAND
length_to_shoulder1.320 INCHES NOMINAL IN
screw_thread_locationINTERNAL
casehardening_indicatorNOT CASEHARDENED
smallest_inside_diameter2.409 INCHES NOMINAL IN
screw_thread_series_designatorUNIFIED NATIONAL JOINT (UNJ)
NSN4730-01-356-1040
COMPONENT DIAGRAM
HOSE FITTING — THREAD TYPE IS CRITICAL END A: — STRAIGHT END B: — SPECIFICATIONS Thread: — Material: — Pressure: — PN: A51K5611-5 · OEM ⚠ VERIFY BEFORE ORDERING NPT ≠ BSPT — tapered threads look identical but are NOT interchangeable. Wrong thread = leak. JIC (37°) ≠ AN (37°) ≠ SAE 45° — flare angles must match exactly. Measure thread pitch with gauge — visual identification is unreliable ✓ BROKER TIP Always use thread sealant (PTFE tape or pipe compound) on tapered threads (NPT/BSPT). JIC/AN flare fittings seal metal-to-metal — never use tape on flare connections PARTSTABLE TECHNICAL DRAWING — NOT TO SCALE
KEY FEATURES
•
LENGTH TO SHOULDER: 1.320 INCHES NOMINAL IN
•
THREAD LENGTH: 0.540 INCHES NOMINAL IN
•
STYLE DESIGNATOR: KNURLED, INTERNAL THREAD, SHOULDERED
•
THREAD DIRECTION: RIGHT-HAND
•
CASEHARDENING INDICATOR: NOT CASEHARDENED
•
THREAD SIZE: 3-16
•
SCREW THREAD SERIES DESIGNATOR: UNIFIED NATIONAL JOINT (UNJ)
TECHNICAL CHARACTERISTICS
LENGTH TO SHOULDER1.320 INCHES NOMINAL IN
THREAD LENGTH0.540 INCHES NOMINAL IN
STYLE DESIGNATORKNURLED, INTERNAL THREAD, SHOULDERED
OVERALL LENGTH1.490 INCHES NOMINAL IN
THREAD DIRECTIONRIGHT-HAND
CASEHARDENING INDICATORNOT CASEHARDENED
THREAD SIZE3-16
SCREW THREAD SERIES DESIGNATORUNIFIED NATIONAL JOINT (UNJ)
THREAD CLASS3B
MAJOR UNTHREADED OUTSIDE DIAMETER3.350 INCHES NOMINAL IN
OTHER ITEMS IN FSC 4730 — Hose, Pipe, Tube, Lubrication, and Railing Fittings
Items in the same Federal Supply class. No interchangeability or substitution relationship is implied.
4730-00-000-1895 4730-00-000-4289 4730-00-000-4445 4730-00-000-8373 4730-00-000-8897 4730-00-001-0007 4730-00-001-0008
SUBSTITUTES & CROSS-REFERENCES 2
A51K56511Reference document
Same NSN cross-reference
Reference document — Drawing number reference only
A51K56511-5Reference document
Same NSN cross-reference
Reference document — Design control — primary reference
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 A51K5611-5?
A51K5611-5 is a PACKING NUT.
What parts can replace A51K5611-5?
There are 2 known substitutes for A51K5611-5: A51K56511, A51K56511-5. Substitute compatibility should be verified for your specific system.
What is the NSN for A51K5611-5?
A51K5611-5 is cataloged in the U.S. Government catalog under NSN 4730-01-356-1040. 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.