PartsTable
Technical Data Sheet
Download PDF

75A550663-2003 — ADAPTER,STRAIGHT,FLANGE TO BOSS

✓ Government record, cited
— · HOSE FITTING
PRODUCT OVERVIEW

75A550663-2003: ADAPTER,STRAIGHT,FLANGE TO BOSS.

ADAPTER,STRAIGHT,FLANGE TO BOSS. Key specifications include material: STEEL OVERALL, flange_shape: ROUND FIRST ENDROUND FIRST END, thread_class: 3A SECOND END3A SECOND END A, connection_type: THREADED EXTERNAL BOSS SECOND ENDTHREADED EXTERNAL BOSS SECOND END, connection_style: EXTERNAL SEAT FOR GASKET SEAL (BOSS) SECOND ENDEXTERNAL SEAT FOR GASKET SEAL (BOSS) SECOND END, nominal_thickness: 0.100 INCHES FIRST END0.100 INCHES FIRST END IN. This part is cataloged in the U.S.

Government catalog under NSN 4730-01-194-5149, 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
75A550663-2003
NSN: 4730-01-194-5149
FSC: 4730 — Hose, Pipe, Tube, Lubrication, and Railing Fittings
CAGE: 76301 — THE BOEING COMPANY DIV DEFENSE (USA)
SPECIFICATIONS
materialSTEEL OVERALL
flange_shapeROUND FIRST ENDROUND FIRST END
thread_class3A SECOND END3A SECOND END A
connection_typeTHREADED EXTERNAL BOSS SECOND ENDTHREADED EXTERNAL BOSS SECOND END
connection_styleEXTERNAL SEAT FOR GASKET SEAL (BOSS) SECOND ENDEXTERNAL SEAT FOR GASKET SEAL (BOSS) SECOND END
special_featuresTHD INT ON FLANGE END 2.125-12UNJ-3B LH;FLIGHT SAFETY CRITICALTHD INT ON FLANGE END 2.125-12UNJ-3B LH;FLIGHT SAFETY CRITICAL
nominal_thickness0.100 INCHES FIRST END0.100 INCHES FIRST END IN
flange_face_designPLAIN FIRST ENDPLAIN FIRST END
nominal_thread_size2.500 INCHES SECOND END2.500 INCHES SECOND END IN
nominal_overall_length2.375 INCHES2.375 INCHES IN
nominal_outside_diameter3.750 INCHES FIRST END3.750 INCHES FIRST END IN
thread_quantity_per_inch12 SECOND END12 SECOND END
NSN4730-01-194-5149
COMPONENT DIAGRAM
HOSE FITTING — THREAD TYPE IS CRITICAL END A: — STRAIGHT END B: — SPECIFICATIONS Thread: — Material: — Pressure: — PN: 75A550663-2003 · 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
•
FLANGE SHAPE: ROUND FIRST ENDROUND FIRST END
•
FURNISHED ITEMS AND QUANTITY: 1 PREFORMED PACKING1 PREFORMED PACKING
•
FLANGE FACE DESIGN: PLAIN FIRST ENDPLAIN FIRST END
•
CONNECTION STYLE: EXTERNAL SEAT FOR GASKET SEAL (BOSS) SECOND ENDEXTERNAL SEAT FOR GASKET SEAL (BOSS) SECOND END
•
NOMINAL OVERALL LENGTH: 2.375 INCHES2.375 INCHES IN
•
CRITICALITY CODE JUSTIFICATION: FEATFEAT
•
CONNECTION TYPE: THREADED EXTERNAL BOSS SECOND ENDTHREADED EXTERNAL BOSS SECOND END
TECHNICAL CHARACTERISTICS
FLANGE SHAPEROUND FIRST ENDROUND FIRST END
FURNISHED ITEMS AND QUANTITY1 PREFORMED PACKING1 PREFORMED PACKING
FLANGE FACE DESIGNPLAIN FIRST ENDPLAIN FIRST END
CONNECTION STYLEEXTERNAL SEAT FOR GASKET SEAL (BOSS) SECOND ENDEXTERNAL SEAT FOR GASKET SEAL (BOSS) SECOND END
NOMINAL OVERALL LENGTH2.375 INCHES2.375 INCHES IN
CRITICALITY CODE JUSTIFICATIONFEATFEAT
CONNECTION TYPETHREADED EXTERNAL BOSS SECOND ENDTHREADED EXTERNAL BOSS SECOND END
CONNECTION TYPEFLANGE FIRST ENDFLANGE FIRST END
MATERIAL DOCUMENT AND CLASSIFICATIONAMS6411 ASSN STD SINGLE MATERIAL RESPONSE OVERALLAMS6411 ASSN STD SINGLE MATERIAL RESPONSE OVERALL
NOMINAL THREAD SIZE2.500 INCHES SECOND END2.500 INCHES SECOND END 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
75A550663Reference document
Same NSN cross-reference
Reference document — Drawing number reference only
75A550663-2001Reference document
Same NSN cross-reference
Reference document — Secondary reference
LIFECYCLE
NSN statusActive· U.S. Government catalog
Acquisition advice: Normally procured from the manufacturer (OEM)No demilitarization required
Ready to buy 75A550663-2003?
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 75A550663-2003?
75A550663-2003 is a ADAPTER,STRAIGHT,FLANGE TO BOSS.
What parts can replace 75A550663-2003?
There are 2 known substitutes for 75A550663-2003: 75A550663, 75A550663-2001. Substitute compatibility should be verified for your specific system.
What is the NSN for 75A550663-2003?
75A550663-2003 is cataloged in the U.S. Government catalog under NSN 4730-01-194-5149. This indicates validated use in U.S. government and defense supply chains.
Community Feedback
Leave a Comment
Comments are reviewed before appearing. You will receive an email to verify before your comment appears.

Request a Quote — 75A550663-2003

✓ 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.