PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

255721 PIECE 89Screw,cap,socket Head

Huntington Ingalls Inc Div Newport News Shipbuilding · NSN 5305-01-432-9645 · FSC 5305 · No Item Name Available
Verified by PartsTable
NSN 5305-01-432-9645 — this item is cataloged by the U.S. Government under National Stock Number 5305-01-432-9645. Primary manufacturer part number: 255721 PIECE 89.
Features
  • Screw,cap,socket Head — FSC 5305
  • Minimum Tensile Strength: 130000 POUNDS PER SQUARE INCH LBS
  • Thread Class: 3A A
  • Minimum Yield Strength: 90000 POUNDS PER SQUARE INCH LBS
  • Nondefinitive Spec/std Data: 6 TYPE AND 500 GRADE
  • Thread Series Designator: UNIFIED NATIONAL COARSE (UNC)
  • Material: NICKEL ALLOY K-500 OVERALL
  • Width Across Flats: 0.188 INCHES NOMINAL IN
Applications
  • Structural fastening and assembly
  • Equipment mounting
  • Panel and housing attachment
  • Applications requiring Nickel Alloy K-500 Overall construction
General Description

The Screw,cap,socket Head, cataloged under National Stock Number 5305-01-432-9645, is classified within Federal Supply Class 5305 (No Item Name Available) of the Hardware and Abrasives group. The primary manufacturer of record is Huntington Ingalls Inc Div Newport News Shipbuilding. Government technical data includes 17 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 5 commercial cross-references from 3 manufacturers, enabling identification through both NSN and commercial part number lookups. 3 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN5305-01-432-9645
Primary Part Number255721 PIECE 89
Item NameScrew,cap,socket Head
FSC / FSG5305 / 53 — No Item Name Available
ManufacturerHuntington Ingalls Inc Div Newport News Shipbuilding
StatusACTIVE
Minimum Tensile Strength130000 POUNDS PER SQUARE INCH LBS
Thread Class3A A
Minimum Yield Strength90000 POUNDS PER SQUARE INCH LBS
Nondefinitive Spec/std Data6 TYPE AND 500 GRADE
Thread Series DesignatorUNIFIED NATIONAL COARSE (UNC)
MaterialNICKEL ALLOY K-500 OVERALL
Width Across Flats0.188 INCHES NOMINAL IN
Nominal Thread Diameter0.250 INCHES IN
Internal Drive StyleHEXAGON
Material Document and ClassificationQQ-N-286 CL A FED SPEC SINGLE MATERIAL RESPONSE OVERALL
Head Diameter0.365 INCHES MINIMUM AND 0.375 INCHES MAXIMUM IN
Thread DirectionRIGHT-HAND
Head StyleFLAT CHAMFER
Thread Quantity Per Inch20
Fastener Length0.500 INCHES NOMINAL IN
Head Height0.244 INCHES MINIMUM AND 0.250 INCHES MAXIMUM IN
Thread Length0.500 INCHES NOMINAL IN
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 3
1660-00-871-0818 INTERCHANGEABLE
Cam,lock
4820-01-430-3675 INTERCHANGEABLE
Valve,ball
5305-01-658-9375 INTERCHANGEABLE
Cap Screw Socket
Cross-Reference Index
Part NumberManufacturer
255721 PIECE 89 PRIMARY Huntington Ingalls Inc Div Newport News Shipbuilding (USA)
255416 PIECE 22 Huntington Ingalls Inc Div Newport News Shipbuilding (USA)
255416 Huntington Ingalls Inc Div Newport News Shipbuilding (USA)
FF-S-86,TY VI,G R 500 Zf Industrieantriebe Witten Gmbh (DEU)
FF-S-86 Federal Specifications Promulgated by General Services Administration Washington DC (USA)
Related Parts
1660-00-871-0818INTERCHANGEABLE
CAM,LOCK
4820-01-430-3675INTERCHANGEABLE
VALVE,BALL
5305-01-658-9375INTERCHANGEABLE
CAP SCREW SOCKET

Frequently Asked Questions

What is NSN 5305-01-432-9645?

NSN 5305-01-432-9645 is a Screw,cap,socket Head, manufactured by Huntington Ingalls Inc Div Newport News Shipbuilding, classified under FSC 5305 (No Item Name Available). Status: active.

What are the part numbers for NSN 5305-01-432-9645?

NSN 5305-01-432-9645 has 5 cross-referenced part numbers: 255721 PIECE 89 (Huntington Ingalls Inc Div Newport News Shipbuilding), 255416 PIECE 22 (Huntington Ingalls Inc Div Newport News Shipbuilding), 255416 (Huntington Ingalls Inc Div Newport News Shipbuilding), FF-S-86,TY VI,G R 500 (Zf Industrieantriebe Witten Gmbh), FF-S-86 (Federal Specifications Promulgated by General Services Administration Washington DC).

What NSN replaces 5305-01-432-9645?

There are 3 known substitutes for 5305-01-432-9645: 1660-00-871-0818, 4820-01-430-3675, 5305-01-658-9375. Verify interchangeability with system specifications before substitution.

What are the specifications of 255721 PIECE 89?

Key specifications for 255721 PIECE 89: Minimum Tensile Strength: 130000 POUNDS PER SQUARE INCH LBS; Thread Class: 3A A; Minimum Yield Strength: 90000 POUNDS PER SQUARE INCH LBS; Nondefinitive Spec/std Data: 6 TYPE AND 500 GRADE. 17 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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