PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

21FK624Nut,self-Locking,hexagon

Sps Technologies, Llc Dba PB Fasteners · NSN 5310-00-865-9889 · FSC 5310 · No Item Name Available
Verified by PartsTable
NSN 5310-00-865-9889 — this item is cataloged by the U.S. Government under National Stock Number 5310-00-865-9889. Primary manufacturer part number: 21FK624.
Features
  • Nut,self-Locking,hexagon — FSC 5310
  • Material: STEEL OVERALL
  • Lubrication: SOLUBLE LUBRICANT
  • Thread Series: UNIFIED NATIONAL JOINT FINE (UNJF)
  • Nominal Thread Size: 0.375 INCHES IN
  • Thread Quantity Per Inch: 24
  • Bearing Surface Type: CHAMFERED
  • Surface Treatment Document and Classification: QQ-P-416,TY 1,CL 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL
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 5310-00-865-9889, 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 14 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 7 commercial cross-references from 6 manufacturers, enabling identification through both NSN and commercial part number lookups. 7 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN5310-00-865-9889
Primary Part Number21FK624
Item NameNut,self-Locking,hexagon
FSC / FSG5310 / 53 — No Item Name Available
ManufacturerSps Technologies, Llc Dba PB Fasteners
StatusACTIVE
MaterialSTEEL OVERALL
LubricationSOLUBLE LUBRICANT
Thread SeriesUNIFIED NATIONAL JOINT FINE (UNJF)
Nominal Thread Size0.375 INCHES IN
Thread Quantity Per Inch24
Bearing Surface TypeCHAMFERED
Surface Treatment Document and ClassificationQQ-P-416,TY 1,CL 3 FED SPEC SINGLE TREATMENT RESPONSE OVERALL
Thread DirectionRIGHT-HAND
Locking FeaturePREVAILING TORQUE ALL METAL DESIGN
Width Across Flats0.553 INCHES MINIMUM AND 0.564 INCHES MAXIMUM IN
Nut Height0.282 INCHES MAXIMUM IN
Surface TreatmentCADMIUM OVERALL
Thread Class3B
Nut StyleHEXAGON
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 7
5330-00-071-4865 INTERCHANGEABLE
Gasket
1710-01-311-854770431 INTERCHANGEABLE
Coller Oil
Curtiss-Wright Flow Control Service, Llc Dba Engineered Arresting Systems - Esco Div Cw Flow Control Svc Llc Dba
5365-01-342-0520 INTERCHANGEABLE
Ring,externally Threaded
5307-01-524-542580129 INTERCHANGEABLE
Stud,plain
Hutchinson Industries, Inc Div Defense and Industry
5120-01-608-290880129 INTERCHANGEABLE
Toggle Lever Assist
Hdt Expeditionary Systems, Inc. Dba Hdt Tactical Systems Inc
5133-01-644-582680129 INTERCHANGEABLE
Drill,twist
Stanley Tools Div of Stanley Works
3438-01-661-966380129 INTERCHANGEABLE
Marker,soapstone
La-Co Industries, Inc. Dba Markal Company
Cross-Reference Index
Part NumberManufacturer
21FK624 Apollo Aerospace Components Llc (USA)
CJ1-21-FK-624 Flowserve Corp Dba Automax Actuators Div Flowserve Us Company (USA)
21FK624 PRIMARY Sps Technologies, Llc Dba PB Fasteners (USA)
120-11000PC37 & Flowserve Corp Dba Automax Actuators Div Flowserve Us Company (USA)
CJ1-20FK-624 Zf Industrieantriebe Witten Gmbh (DEU)
21FK624 Sps Technologies Inc (USA)
80129 Federal Screw Products, Inc. (USA)
Related Parts
5330-00-071-4865INTERCHANGEABLE
GASKET
1710-01-311-8547INTERCHANGEABLE
COLLER OIL
70431
5365-01-342-0520INTERCHANGEABLE
RING,EXTERNALLY THREADED
5307-01-524-5425INTERCHANGEABLE
STUD,PLAIN
80129
5120-01-608-2908INTERCHANGEABLE
TOGGLE LEVER ASSIST
80129
5133-01-644-5826INTERCHANGEABLE
DRILL,TWIST
80129
3438-01-661-9663INTERCHANGEABLE
MARKER,SOAPSTONE
80129

Frequently Asked Questions

What is NSN 5310-00-865-9889?

NSN 5310-00-865-9889 is a Nut,self-Locking,hexagon, manufactured by Sps Technologies, Llc Dba PB Fasteners, classified under FSC 5310 (No Item Name Available). Status: active.

What are the part numbers for NSN 5310-00-865-9889?

NSN 5310-00-865-9889 has 7 cross-referenced part numbers: 21FK624 (Apollo Aerospace Components Llc), CJ1-21-FK-624 (Flowserve Corp Dba Automax Actuators Div Flowserve Us Company), 21FK624 (Sps Technologies, Llc Dba PB Fasteners), 120-11000PC37 & (Flowserve Corp Dba Automax Actuators Div Flowserve Us Company), CJ1-20FK-624 (Zf Industrieantriebe Witten Gmbh) and 2 more.

What NSN replaces 5310-00-865-9889?

There are 7 known substitutes for 5310-00-865-9889: 5330-00-071-4865, 1710-01-311-8547, 5365-01-342-0520 and 4 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 21FK624?

Key specifications for 21FK624: Material: STEEL OVERALL; Lubrication: SOLUBLE LUBRICANT; Thread Series: UNIFIED NATIONAL JOINT FINE (UNJF); Nominal Thread Size: 0.375 INCHES IN. 14 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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