PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

6191Nut,tube Coupling

Cae Usa Inc. · NSN 4730-00-278-5451 · FSC 4730 · No Item Name Available
Verified by PartsTable
NSN 4730-00-278-5451 — this item is cataloged by the U.S. Government under National Stock Number 4730-00-278-5451. Primary manufacturer part number: 6191.
Features
  • Nut,tube Coupling — FSC 4730
  • Nominal Tube Outside Diameter: 0.250 INCHES IN
  • Thread Series: UNF
  • Nominal Thread Size: 0.438 INCHES IN
  • Material: COPPER ALLOY OVERALL
  • Material Document and Classification: QQ-B-626,CP 21 OR 22 FED SPEC SINGLE MATERIAL RESPONSE OVERALL
  • Width Across Flats: 0.556 INCHES MINIMUM AND 0.565 INCHES MAXIMUM IN
  • Nut Height: 0.500 INCHES NOMINAL IN
Applications
  • Structural fastening and assembly
  • Equipment mounting
  • Panel and housing attachment
  • Fluid conveyance
  • Hydraulic system plumbing
General Description

The Nut,tube Coupling, cataloged under National Stock Number 4730-00-278-5451, is classified within Federal Supply Class 4730 (No Item Name Available) of the Pipe, Tubing, Hose, and Fittings group. The primary manufacturer of record is Cae Usa Inc.. Government technical data includes 14 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 11 commercial cross-references from 11 manufacturers, enabling identification through both NSN and commercial part number lookups. 12 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Cancelled.

Technical Specifications
ParameterValue
NSN4730-00-278-5451
Primary Part Number6191
Item NameNut,tube Coupling
FSC / FSG4730 / 47 — No Item Name Available
ManufacturerCae Usa Inc.
StatusCANCELLED
Nominal Tube Outside Diameter0.250 INCHES IN
Thread SeriesUNF
Nominal Thread Size0.438 INCHES IN
MaterialCOPPER ALLOY OVERALL
Material Document and ClassificationQQ-B-626,CP 21 OR 22 FED SPEC SINGLE MATERIAL RESPONSE OVERALL
Width Across Flats0.556 INCHES MINIMUM AND 0.565 INCHES MAXIMUM IN
Nut Height0.500 INCHES NOMINAL IN
Length to Shoulder0.370 INCHES MINIMUM AND 0.380 INCHES MAXIMUM IN
Thread DirectionRIGHT-HAND
Thread Quantity Per Inch20
Thread Class3B
Fabrication MethodMACHINED
Nut StyleTUBE COUPLING
Smallest Inside Diameter0.316 INCHES MINIMUM AND 0.320 INCHES MAXIMUM IN
Lifecycle & Compliance
Acquisition StatusCANCELLED
HAZMATNo
Verified Substitutes 12
5910-00-100-5727306-67-4M INTERCHANGEABLE
Capacitor,fixed,paper Dielectric
General Instrument Corp Corporate Headquarters
5940-00-114-1317 INTERCHANGEABLE
Terminal,lug
5330-00-154-74066191 INTERCHANGEABLE
Seal,plain Encased
Skf Usa Inc. Dba Skf Aerospace Sealing Solutions
8115-00-179-057918X12X10SWDOM275 INTERCHANGEABLE
Box,shipping
Ponderosa Packaging Corp.
3030-00-180-671429-13245-00 INTERCHANGEABLE
Belt,flat
Compaq Federal Llc
5330-00-189-8909SCD1640ITEM38 INTERCHANGEABLE
Gasket
Us Army Communications & Electronics Materiel Readiness Command Logistics Engineering Dir
5950-00-238-020014827 INTERCHANGEABLE
Transformer,audio Frequency
Dukane Seacom, Inc. Dba Dukane Seacom Inc
5905-00-280-15840579 INTERCHANGEABLE
Resistor,adjustable
Stewart & Stevenson Power Products Llc
6145-00-284-0660SAE-J1128 TYPE SXL 14AWG-BLACK INTERCHANGEABLE
Wire,electrical
Sae International Dba Sae International
6105-00-407-3906 INTERCHANGEABLE
Insulator,holder As
Cross-Reference Index
Part NumberManufacturer
6191 Cae Usa Inc. (USA)
AN805-4 Aeronautical Standards Group Dept of Navy and Air Force (USA)
6191 Raytheon Technical Services Company (USA)
200230 Renk America Llc Div Renk America (USA)
14827 Pratt & Whitney Canada Corp Div Pratt & Whitney Canada Corp. (CAN)
MIL-DTL-6001 Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M
156D3 Curtiss-Wright Controls, Inc. Div Actuation Division (USA)
AN805-4 Air Force-Navy Aeronautical Specifications Promulgated by Aeronautical Standards Group
0579 Lawrence Aeronautical Corp (USA)
7376064 U S Army Tank Automotive Command Amsta-Im-Mm (USA)
156D3 Curtiss-Wright Corp (USA)
Related Parts
5910-00-100-5727INTERCHANGEABLE
CAPACITOR,FIXED,PAPER DIELECTRIC
306-67-4M
5940-00-114-1317INTERCHANGEABLE
TERMINAL,LUG
5330-00-154-7406INTERCHANGEABLE
SEAL,PLAIN ENCASED
6191
8115-00-179-0579INTERCHANGEABLE
BOX,SHIPPING
18X12X10SWDOM275
3030-00-180-6714INTERCHANGEABLE
BELT,FLAT
29-13245-00
5330-00-189-8909INTERCHANGEABLE
GASKET
SCD1640ITEM38
5950-00-238-0200INTERCHANGEABLE
TRANSFORMER,AUDIO FREQUENCY
14827
5905-00-280-1584INTERCHANGEABLE
RESISTOR,ADJUSTABLE
0579
6145-00-284-0660INTERCHANGEABLE
WIRE,ELECTRICAL
SAE-J1128 TYPE SXL 14AWG-BLACK
6105-00-407-3906INTERCHANGEABLE
INSULATOR,HOLDER AS
5330-00-526-7025INTERCHANGEABLE
GASKET
6191
5950-00-600-0840INTERCHANGEABLE
TRANSFORMER,POWER
72-2609

Frequently Asked Questions

What is NSN 4730-00-278-5451?

NSN 4730-00-278-5451 is a Nut,tube Coupling, manufactured by Cae Usa Inc., classified under FSC 4730 (No Item Name Available). Status: cancelled.

What are the part numbers for NSN 4730-00-278-5451?

NSN 4730-00-278-5451 has 11 cross-referenced part numbers: 6191 (Cae Usa Inc.), AN805-4 (Aeronautical Standards Group Dept of Navy and Air Force), 6191 (Raytheon Technical Services Company), 200230 (Renk America Llc Div Renk America), 14827 (Pratt & Whitney Canada Corp Div Pratt & Whitney Canada Corp.) and 6 more.

What NSN replaces 4730-00-278-5451?

There are 12 known substitutes for 4730-00-278-5451: 5910-00-100-5727, 5940-00-114-1317, 5330-00-154-7406 and 9 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 6191?

Key specifications for 6191: Nominal Tube Outside Diameter: 0.250 INCHES IN; Thread Series: UNF; Nominal Thread Size: 0.438 INCHES IN; Material: COPPER ALLOY OVERALL. 14 total characteristics are documented in the Federal Logistics Information System.

Is NSN 4730-00-278-5451 still in active supply?

NSN 4730-00-278-5451 is currently cancelled. Check with the Defense Logistics Agency for current availability and authorized substitutes.

Validated with multiple authoritative sources, including Government, OEM, and Certified sources.
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