PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

AA557D4Nut,tube Coupling

Allan Aircraft Supply Co., Llc Dba Allan Aircraft Supply · NSN 4730-00-908-6926 · FSC 4730 · No Item Name Available
Verified by PartsTable
NSN 4730-00-908-6926 — this item is cataloged by the U.S. Government under National Stock Number 4730-00-908-6926. Primary manufacturer part number: AA557D4.
Features
  • Nut,tube Coupling — FSC 4730
  • Smallest Inside Diameter: 0.305 INCHES NOMINAL IN
  • Surface Treatment: ANODIZE OVERALL
  • Nut Height: 0.620 INCHES NOMINAL IN
  • Material: ALUMINUM ALLOY OVERALL
  • Thread Series: UNF
  • Nominal Tube Outside Diameter: 0.250 INCHES IN
  • Width Across Flats: 0.543 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 4730-00-908-6926, 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 Allan Aircraft Supply Co., Llc Dba Allan Aircraft Supply. Government technical data includes 13 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 12 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: Active.

Technical Specifications
ParameterValue
NSN4730-00-908-6926
Primary Part NumberAA557D4
Item NameNut,tube Coupling
FSC / FSG4730 / 47 — No Item Name Available
ManufacturerAllan Aircraft Supply Co., Llc Dba Allan Aircraft Supply
StatusACTIVE
Smallest Inside Diameter0.305 INCHES NOMINAL IN
Surface TreatmentANODIZE OVERALL
Nut Height0.620 INCHES NOMINAL IN
MaterialALUMINUM ALLOY OVERALL
Thread SeriesUNF
Nominal Tube Outside Diameter0.250 INCHES IN
Width Across Flats0.543 INCHES NOMINAL IN
Length to Shoulder0.532 INCHES NOMINAL IN
Nut StyleTUBE COUPLING
Nominal Thread Size0.438 INCHES IN
Thread Quantity Per Inch20
Thread DirectionLEFT-HAND
Thread Class3B
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 12
3110-00-156-7513 INTERCHANGEABLE
Bearing,ball,annular
5365-00-188-8280 INTERCHANGEABLE
Spacer,ring
3110-00-785-6496 INTERCHANGEABLE
Bearing,roller,tapered
5940-00-904-96241110-16-59 INTERCHANGEABLE
Terminal,feedthru
Concord Electronics, Inc.
5975-01-064-6415IH3-1-LM INTERCHANGEABLE
Conduit Outlet
Abb Installation Products Inc
5975-01-238-463030203 INTERCHANGEABLE
Conduit Outlet
Hubbell-Raco Inc
2530-01-249-157712460467-1 INTERCHANGEABLE
Idler Arm,steering,vehicular
U S Army Tank Automotive Command Amsta-Im-Mm
4820-01-262-0799 INTERCHANGEABLE
Valve,regulating,fluid Pressure
5307-01-328-1003 INTERCHANGEABLE
Stud,ball
2540-01-343-217830203 INTERCHANGEABLE
Screen,core
Hdt Expeditionary Systems Inc
Cross-Reference Index
Part NumberManufacturer
AA557D4 PRIMARY Allan Aircraft Supply Co., Llc Dba Allan Aircraft Supply (USA)
1-03028D4 PRIMARY Eaton Aeroquip Llc Dba Jackson North 1 Div Fluid and Electrical Distribution (USA)
105-01557-19004 Danfoss Power Solutions II, Llc (USA)
30203 Faber Enterprises, Inc. Div Faber Enterprise Inc (USA)
105-01557-19004 Designed Metal Connections Inc Dba Permaswage Usa Div Permaswage, a Pcc Company (USA)
105-01557-19004 Dana Corp Weatherhead Div (USA)
11D4D4 Designed Metal Connections Inc Dba Permaswage Usa Div Permaswage, a Pcc Company (USA)
C557D4 PRIMARY Lockheed Martin Corporation Div Lockheed Martin Aeronautics Company (USA)
5069D4 Tech Aero Inc (USA)
111557D4 Huck International, Inc (USA)
GA7080D4 Globe Aerospace Inc (USA)
111557D4 Huck Intl Inc (USA)
Related Parts
3110-00-156-7513INTERCHANGEABLE
BEARING,BALL,ANNULAR
5365-00-188-8280INTERCHANGEABLE
SPACER,RING
3110-00-785-6496INTERCHANGEABLE
BEARING,ROLLER,TAPERED
5940-00-904-9624INTERCHANGEABLE
TERMINAL,FEEDTHRU
1110-16-59
5975-01-064-6415INTERCHANGEABLE
CONDUIT OUTLET
IH3-1-LM
5975-01-238-4630INTERCHANGEABLE
CONDUIT OUTLET
30203
2530-01-249-1577INTERCHANGEABLE
IDLER ARM,STEERING,VEHICULAR
12460467-1
4820-01-262-0799INTERCHANGEABLE
VALVE,REGULATING,FLUID PRESSURE
5307-01-328-1003INTERCHANGEABLE
STUD,BALL
2540-01-343-2178INTERCHANGEABLE
SCREEN,CORE
30203
5365-01-418-0601INTERCHANGEABLE
PLUG,MACHINE THREAD
30203
5210-01-654-5640INTERCHANGEABLE
SQUARE,THIN STEEL
3020-3

Frequently Asked Questions

What is NSN 4730-00-908-6926?

NSN 4730-00-908-6926 is a Nut,tube Coupling, manufactured by Allan Aircraft Supply Co., Llc Dba Allan Aircraft Supply, classified under FSC 4730 (No Item Name Available). Status: active.

What are the part numbers for NSN 4730-00-908-6926?

NSN 4730-00-908-6926 has 12 cross-referenced part numbers: AA557D4 (Allan Aircraft Supply Co., Llc Dba Allan Aircraft Supply), 1-03028D4 (Eaton Aeroquip Llc Dba Jackson North 1 Div Fluid and Electrical Distribution), 105-01557-19004 (Danfoss Power Solutions II, Llc), 30203 (Faber Enterprises, Inc. Div Faber Enterprise Inc), 105-01557-19004 (Designed Metal Connections Inc Dba Permaswage Usa Div Permaswage, a Pcc Company) and 7 more.

What NSN replaces 4730-00-908-6926?

There are 12 known substitutes for 4730-00-908-6926: 3110-00-156-7513, 5365-00-188-8280, 3110-00-785-6496 and 9 more. Verify interchangeability with system specifications before substitution.

What are the specifications of AA557D4?

Key specifications for AA557D4: Smallest Inside Diameter: 0.305 INCHES NOMINAL IN; Surface Treatment: ANODIZE OVERALL; Nut Height: 0.620 INCHES NOMINAL IN; Material: ALUMINUM ALLOY OVERALL. 13 total characteristics are documented in the Federal Logistics Information System.

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