PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

21FA420Nut,self-Locking,hexagon

Sps Technologies, Llc Dba PB Fasteners · NSN 5310-00-706-0785 · FSC 5310 · No Item Name Available
Verified by PartsTable
NSN 5310-00-706-0785 — this item is cataloged by the U.S. Government under National Stock Number 5310-00-706-0785. Primary manufacturer part number: 21FA420.
Features
  • Nut,self-Locking,hexagon — FSC 5310
  • Width Across Flats: 0.430 INCHES MINIMUM AND 0.439 INCHES MAXIMUM IN
  • Surface Treatment Document and Classification: QQ-P-416,TY 1,CL 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL
  • Nominal Thread Size: 0.250 INCHES IN
  • Bearing Surface Type: CHAMFERED
  • Thread Series: UNIFIED NATIONAL COARSE (UNC)
  • Thread Quantity Per Inch: 20
  • Nut Height: 0.270 INCHES MINIMUM AND 0.290 INCHES MAXIMUM IN
Applications
  • Structural fastening and assembly
  • Equipment mounting
  • Panel and housing attachment
  • Applications requiring Steel Overall construction
General Description

The Nut,self-Locking,hexagon, cataloged under National Stock Number 5310-00-706-0785, is classified within Federal Supply Class 5310 (No Item Name Available) of the Hardware and Abrasives group. The primary manufacturer of record is Sps Technologies, Llc Dba PB Fasteners. Government technical data includes 13 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 4 commercial cross-references from 4 manufacturers, enabling identification through both NSN and commercial part number lookups. 2 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Cancelled.

Technical Specifications
ParameterValue
NSN5310-00-706-0785
Primary Part Number21FA420
Item NameNut,self-Locking,hexagon
FSC / FSG5310 / 53 — No Item Name Available
ManufacturerSps Technologies, Llc Dba PB Fasteners
StatusCANCELLED
Width Across Flats0.430 INCHES MINIMUM AND 0.439 INCHES MAXIMUM IN
Surface Treatment Document and ClassificationQQ-P-416,TY 1,CL 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL
Nominal Thread Size0.250 INCHES IN
Bearing Surface TypeCHAMFERED
Thread SeriesUNIFIED NATIONAL COARSE (UNC)
Thread Quantity Per Inch20
Nut Height0.270 INCHES MINIMUM AND 0.290 INCHES MAXIMUM IN
Locking FeaturePREVAILING TORQUE ALL METAL DESIGN
Surface TreatmentCADMIUM OVERALL
Thread DirectionRIGHT-HAND
Thread Class2B
Nut StyleHEXAGON
MaterialSTEEL OVERALL
Lifecycle & Compliance
Acquisition StatusCANCELLED
HAZMATNo
Verified Substitutes 2
5310-00-575-562821FA-420 INTERCHANGEABLE
Nut,self-Locking,hexagon
Sps Technologies, Llc Dba PB Fasteners
4730-01-619-05102201/0016 INTERCHANGEABLE
Clamp,hose
Jcb Inc.
Cross-Reference Index
Part NumberManufacturer
21FA420 PRIMARY Sps Technologies, Llc Dba PB Fasteners (USA)
5310PL0625588 Jednolity Indeks Materialowy - Uniform Material Index (POL)
220100-16 Kearfott Corporation Div Guidance and Navigation Division (USA)
149520007 D & J Parts Inc (USA)
Related Parts
5310-00-575-5628INTERCHANGEABLE
NUT,SELF-LOCKING,HEXAGON
21FA-420
4730-01-619-0510INTERCHANGEABLE
CLAMP,HOSE
2201/0016

Frequently Asked Questions

What is NSN 5310-00-706-0785?

NSN 5310-00-706-0785 is a Nut,self-Locking,hexagon, manufactured by Sps Technologies, Llc Dba PB Fasteners, classified under FSC 5310 (No Item Name Available). Status: cancelled.

What are the part numbers for NSN 5310-00-706-0785?

NSN 5310-00-706-0785 has 4 cross-referenced part numbers: 21FA420 (Sps Technologies, Llc Dba PB Fasteners), 5310PL0625588 (Jednolity Indeks Materialowy - Uniform Material Index), 220100-16 (Kearfott Corporation Div Guidance and Navigation Division), 149520007 (D & J Parts Inc).

What NSN replaces 5310-00-706-0785?

There are 2 known substitutes for 5310-00-706-0785: 5310-00-575-5628, 4730-01-619-0510. Verify interchangeability with system specifications before substitution.

What are the specifications of 21FA420?

Key specifications for 21FA420: Width Across Flats: 0.430 INCHES MINIMUM AND 0.439 INCHES MAXIMUM IN; Surface Treatment Document and Classification: QQ-P-416,TY 1,CL 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Nominal Thread Size: 0.250 INCHES IN; Bearing Surface Type: CHAMFERED. 13 total characteristics are documented in the Federal Logistics Information System.

Is NSN 5310-00-706-0785 still in active supply?

NSN 5310-00-706-0785 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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