PartsTable
Technical Data Sheet
PartsTable / COMPONENT / MB-19-K5
MB-19-K5 ✓ Verified by PartsTable
— · HOSE FITTING
WHAT YOU NEED TO KNOW
PTFE tape on tapered threads (NPT/BSPT) JIC/AN flare connections seal metal-to-metal — no tape
NPT != BSPT — look identical, NOT interchangeable
PRODUCT OVERVIEW

The PACKING NUT is a the manufacturer industrial component. Key specifications include material: STEEL CORROSION RESISTING, thread_size: 0.438-24, thread_class: 2A A, thread_length: 0.188 INCHES NOMINAL IN, overall_length: 0.469 INCHES NOMINAL IN, style_designator: HEXAGON, EXTERNAL THREAD, INVERTED FLARE. This product is currently in active production with full OEM support.

This part is cataloged in the Federal Logistics Information System (FLIS) under NSN 4730-00-422-8789, 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
MB-19-K5
NSN: 4730-00-422-8789
FSC: 4730
CAGE: 17431 — ILLINOIS TOOL WORKS INC. (USA)
SPECIFICATIONS
materialSTEEL CORROSION RESISTING
thread_size0.438-24
thread_class2A A
thread_length0.188 INCHES NOMINAL IN
overall_length0.469 INCHES NOMINAL IN
style_designatorHEXAGON, EXTERNAL THREAD, INVERTED FLARE
thread_directionRIGHT-HAND
seat_angle_in_deg60.0
width_across_flats0.500 INCHES NOMINAL IN
screw_thread_locationEXTERNAL
casehardening_indicatorNOT CASEHARDENED
smallest_inside_diameter0.141 INCHES NOMINAL IN
NSN4730-00-422-8789
COMPONENT DIAGRAM
HOSE FITTING — THREAD TYPE IS CRITICAL END A: — STRAIGHT END B: — SPECIFICATIONS Thread: — Material: — Pressure: — PN: MB-19-K5 · 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
•
THREAD CLASS: 2A A
•
CASEHARDENING INDICATOR: NOT CASEHARDENED
•
SMALLEST INSIDE DIAMETER: 0.141 INCHES NOMINAL IN
•
WIDTH ACROSS FLATS: 0.500 INCHES NOMINAL IN
•
SCREW THREAD LOCATION: EXTERNAL
•
STYLE DESIGNATOR: HEXAGON, EXTERNAL THREAD, INVERTED FLARE
•
MATERIAL: STEEL CORROSION RESISTING
TECHNICAL CHARACTERISTICS (FLIS)
OVERALL LENGTH0.469 INCHES NOMINAL IN
THREAD CLASS2A A
CASEHARDENING INDICATORNOT CASEHARDENED
SMALLEST INSIDE DIAMETER0.141 INCHES NOMINAL IN
WIDTH ACROSS FLATS0.500 INCHES NOMINAL IN
SCREW THREAD LOCATIONEXTERNAL
STYLE DESIGNATORHEXAGON, EXTERNAL THREAD, INVERTED FLARE
MATERIALSTEEL CORROSION RESISTING
SEAT ANGLE IN DEG60.0
SCREW THREAD SERIES DESIGNATORUNS
VERIFIED SUBSTITUTES & CROSS-REFERENCES 4
MILG26727Interchangeable
interchangeable cross-reference
interchangeable
55D6246-1Interchangeable
interchangeable cross-reference
interchangeable
MB19Interchangeable
interchangeable cross-reference
interchangeable
66D44469-501Interchangeable
interchangeable cross-reference
interchangeable
LIFECYCLE
StatusACTIVE
AvailabilityOEM and secondary market
RoHS CompliantEAR99Not HAZMAT
Ready to buy MB-19-K5?
Compare prices from verified sellers on eBay
Buy on eBay →
As an eBay Partner, PartsTable may earn a commission. Your price is not affected.
FREQUENTLY ASKED QUESTIONS
What is MB-19-K5?
MB-19-K5 is a PACKING NUT.
What parts can replace MB-19-K5?
There are 4 known substitutes for MB-19-K5: MILG26727, 55D6246-1, MB19 and 1 more. Substitute compatibility should be verified for your specific system.
What is the NSN for MB-19-K5?
MB-19-K5 is cataloged in the Federal Logistics Information System (FLIS) under NSN 4730-00-422-8789. This indicates validated use in U.S. government and defense supply chains.
Community Feedback
Comments (0)
No comments yet. Be the first to share what you know.
Leave a Comment
Comments are reviewed before appearing. You will receive an email to verify before your comment appears.

Request a Quote — MB-19-K5

✓ Validated with multiple authoritative sources, including Government, OEM, and Certified sources.
PartsTable Design LLC · partstable.com
Last verified: July 2026