PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

A-A-2171Extension,socket Wrench

Federal Commercial Item Description Promulgated by General Services Administration Washington DC · NSN 5120-01-021-2683 · FSC 5120 · No Item Name Available
Verified by PartsTable
NSN 5120-01-021-2683 — this item is cataloged by the U.S. Government under National Stock Number 5120-01-021-2683. Primary manufacturer part number: A-A-2171.
Features
  • Extension,socket Wrench — FSC 5120
  • Drive Surface Size: 0.250 INCHES NOMINAL BOTH ENDS IN
  • Drive End Shape: SQUARE FIRST END INTERNAL
  • Drive End Shape: SQUARE SECOND END EXTERNAL
  • Outside Diameter: 0.438 INCHES NOMINAL IN
  • Material: STEEL OVERALL
  • Nondefinitive Spec/std Data: 2 TYPE AND 2 CLASS AND B STYLE
  • Surface Treatment: CHROMIUM OVERALL
Applications
  • Applications requiring Steel Overall construction
General Description

The Extension,socket Wrench, cataloged under National Stock Number 5120-01-021-2683, is classified within Federal Supply Class 5120 (No Item Name Available) of the Hand Tools group. The primary manufacturer of record is Federal Commercial Item Description Promulgated by General Services Administration Washington DC. Government technical data includes 9 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 9 commercial cross-references from 7 manufacturers, enabling identification through both NSN and commercial part number lookups. 8 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN5120-01-021-2683
Primary Part NumberA-A-2171
Item NameExtension,socket Wrench
FSC / FSG5120 / 51 — No Item Name Available
ManufacturerFederal Commercial Item Description Promulgated by General Services Administration Washington DC
StatusACTIVE
Drive Surface Size0.250 INCHES NOMINAL BOTH ENDS IN
Drive End ShapeSQUARE FIRST END INTERNAL
Drive End ShapeSQUARE SECOND END EXTERNAL
Outside Diameter0.438 INCHES NOMINAL IN
MaterialSTEEL OVERALL
Nondefinitive Spec/std Data2 TYPE AND 2 CLASS AND B STYLE
Surface TreatmentCHROMIUM OVERALL
Specification/standard Data05047-ASME B107.110 CAT 10 PROFESSIONAL/INDUSTRIAL ASSOCIATION STANDARD
Style DesignatorFLEXIBLE
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 8
5120-00-022-9797 INTERCHANGEABLE
Extension,socket Wrench
3110-00-198-2253 INTERCHANGEABLE
Bearing,ball,annular
5120-00-240-1532 INTERCHANGEABLE
Extension,socket Wrench
5340-01-185-3938RE-B102258 INTERCHANGEABLE
Crank,hand
Naval Sea Systems Command
5120-01-335-1075TM61A INTERCHANGEABLE
Extension,socket Wrench
Idsc Holdings Llc Div Snap-on Industrial, a Div. of Idsc Holdings , Llc
5120-01-398-7708 INTERCHANGEABLE
Extension,socket Wrench
5120-01-399-9526 INTERCHANGEABLE
Extension,socket Wrench
5120-01-430-0620MF4 INTERCHANGEABLE
Extension,socket Wrench
Matco Tools Corp Div Matco Tools
Cross-Reference Index
Part NumberManufacturer
A-A-2171 Federal Commercial Item Description Promulgated by General Services Administration Washington DC (USA)
MF4 Stanley Industrial & Automotive Llc (USA)
MF4 Matco Tools Corp Div Matco Tools (USA)
GGG-W-641 Federal Specifications Promulgated by General Services Administration Washington DC (USA)
B107.10 The American Society of Mechanical Engineers (USA)
2993752-4 Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier (USA)
B107.110 The American Society of Mechanical Engineers (USA)
B107.10 TY2CL2STB General Services Administration Federal Supply Service (USA)
B107.110 CAT 10 TY2CL2STB General Services Administration Federal Supply Service (USA)
Related Parts
5120-00-022-9797INTERCHANGEABLE
EXTENSION,SOCKET WRENCH
3110-00-198-2253INTERCHANGEABLE
BEARING,BALL,ANNULAR
5120-00-240-1532INTERCHANGEABLE
EXTENSION,SOCKET WRENCH
5340-01-185-3938INTERCHANGEABLE
CRANK,HAND
RE-B102258
5120-01-335-1075INTERCHANGEABLE
EXTENSION,SOCKET WRENCH
TM61A
5120-01-398-7708INTERCHANGEABLE
EXTENSION,SOCKET WRENCH
5120-01-399-9526INTERCHANGEABLE
EXTENSION,SOCKET WRENCH
5120-01-430-0620INTERCHANGEABLE
EXTENSION,SOCKET WRENCH
MF4

Frequently Asked Questions

What is NSN 5120-01-021-2683?

NSN 5120-01-021-2683 is a Extension,socket Wrench, manufactured by Federal Commercial Item Description Promulgated by General Services Administration Washington DC, classified under FSC 5120 (No Item Name Available). Status: active.

What are the part numbers for NSN 5120-01-021-2683?

NSN 5120-01-021-2683 has 9 cross-referenced part numbers: A-A-2171 (Federal Commercial Item Description Promulgated by General Services Administration Washington DC), MF4 (Stanley Industrial & Automotive Llc), MF4 (Matco Tools Corp Div Matco Tools), GGG-W-641 (Federal Specifications Promulgated by General Services Administration Washington DC), B107.10 (The American Society of Mechanical Engineers) and 4 more.

What NSN replaces 5120-01-021-2683?

There are 8 known substitutes for 5120-01-021-2683: 5120-00-022-9797, 3110-00-198-2253, 5120-00-240-1532 and 5 more. Verify interchangeability with system specifications before substitution.

What are the specifications of A-A-2171?

Key specifications for A-A-2171: Drive Surface Size: 0.250 INCHES NOMINAL BOTH ENDS IN; Drive End Shape: SQUARE FIRST END INTERNAL; Drive End Shape: SQUARE SECOND END EXTERNAL; Outside Diameter: 0.438 INCHES NOMINAL IN. 10 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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