PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

MILT0021309Expander Tool

Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M · NSN 5120-00-090-4398 · FSC 5120 · No Item Name Available
Verified by PartsTable
NSN 5120-00-090-4398 — this item is cataloged by the U.S. Government under National Stock Number 5120-00-090-4398. Primary manufacturer part number: MILT0021309.
Features
  • Expander Tool — FSC 5120
  • Reference Number Differentiating Characteristics: TYPE III,CLASS 3,THD SIZE 14-1.25MM MM
  • 2 verified cross-references
  • Primary manufacturer: Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M
Applications
  • Field maintenance and repair
  • Facility maintenance operations
  • General-purpose hand tools
General Description

The Expander Tool, cataloged under National Stock Number 5120-00-090-4398, is classified within Federal Supply Class 5120 (No Item Name Available) of the Hand Tools group. The primary manufacturer of record is Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M. Government technical data includes 1 verified specification, sourced from the Federal Logistics Information System (FLIS). This item has 2 commercial cross-references from 2 manufacturers, enabling identification through both NSN and commercial part number lookups. 1 verified substitute exists in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN5120-00-090-4398
Primary Part NumberMILT0021309
Item NameExpander Tool
FSC / FSG5120 / 51 — No Item Name Available
ManufacturerMilitary Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M
StatusACTIVE
Reference Number Differentiating CharacteristicsTYPE III,CLASS 3,THD SIZE 14-1.25MM MM
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 1
5120-00-090-4399468 INTERCHANGEABLE
Tool
Stanley Engineered Fastening Llc
Cross-Reference Index
Part NumberManufacturer
MILT0021309 Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M
436 Stanley Engineered Fastening Llc (USA)
Related Parts
5120-00-090-4399INTERCHANGEABLE
TOOL
468

Frequently Asked Questions

What is NSN 5120-00-090-4398?

NSN 5120-00-090-4398 is a Expander Tool, manufactured by Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M, classified under FSC 5120 (No Item Name Available). Status: active.

What are the part numbers for NSN 5120-00-090-4398?

NSN 5120-00-090-4398 has 2 cross-referenced part numbers: MILT0021309 (Military Specifications Promulgated by Military Departments/agencies Under Authority of Defense Standardization Manual 4120 3-M), 436 (Stanley Engineered Fastening Llc).

What NSN replaces 5120-00-090-4398?

There is 1 known substitute for 5120-00-090-4398: 5120-00-090-4399. Verify interchangeability with system specifications before substitution.

What are the specifications of MILT0021309?

Key specifications for MILT0021309: Reference Number Differentiating Characteristics: TYPE III,CLASS 3,THD SIZE 14-1.25MM MM. 1 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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