PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

18277R1Nut,plain,hexagon

Navistar Intl Corp Melrose Park Engine Plant Location /melrose Park/ · NSN 5310-00-266-0377 · FSC 5310 · No Item Name Available
Verified by PartsTable
NSN 5310-00-266-0377 — this item is cataloged by the U.S. Government under National Stock Number 5310-00-266-0377. Primary manufacturer part number: 18277R1.
Features
  • Nut,plain,hexagon — FSC 5310
  • Thread Direction: LEFT-HAND
  • Bearing Surface Type: WASHER FACED
  • Thread Quantity Per Inch: 13
  • Thread Series: UNIFIED NATIONAL COARSE (UNC)
  • Nominal Thread Size: 0.500 INCHES IN
  • Material: STEEL OVERALL
  • Nondefinitive Spec/std Data: A2 TYPE AND C CLASS
Applications
  • Structural fastening and assembly
  • Equipment mounting
  • Panel and housing attachment
  • Applications requiring Steel Overall construction
General Description

The Nut,plain,hexagon, cataloged under National Stock Number 5310-00-266-0377, is classified within Federal Supply Class 5310 (No Item Name Available) of the Hardware and Abrasives group. The primary manufacturer of record is Navistar Intl Corp Melrose Park Engine Plant Location /melrose Park/. Government technical data includes 11 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. 5 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN5310-00-266-0377
Primary Part Number18277R1
Item NameNut,plain,hexagon
FSC / FSG5310 / 53 — No Item Name Available
ManufacturerNavistar Intl Corp Melrose Park Engine Plant Location /melrose Park/
StatusACTIVE
Thread DirectionLEFT-HAND
Bearing Surface TypeWASHER FACED
Thread Quantity Per Inch13
Thread SeriesUNIFIED NATIONAL COARSE (UNC)
Nominal Thread Size0.500 INCHES IN
MaterialSTEEL OVERALL
Nondefinitive Spec/std DataA2 TYPE AND C CLASS
Nut StyleHEXAGON
Nut Height0.402 INCHES MINIMUM AND 0.442 INCHES MAXIMUM IN
Width Across Flats0.7880 INCHES MINIMUM AND 0.8125 INCHES MAXIMUM IN
Thread Class2B
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 5
5310-00-265-9217 INTERCHANGEABLE
Nut,plain,hexagon
5310-00-265-9221 INTERCHANGEABLE
Nut,plain,hexagon
5310-00-265-9222 INTERCHANGEABLE
Nut,plain,hexagon
5310-00-266-0379 INTERCHANGEABLE
Nut,plain,hexagon
5310-00-266-0380 INTERCHANGEABLE
Nut,plain,hexagon
Cross-Reference Index
Part NumberManufacturer
18277R1 Navistar Intl Corp Melrose Park Engine Plant Location /melrose Park/ (USA)
18277R1 Navistar International Corporation Dba Navistar (USA)
18277R1 International Harvester Co Agricultural Equipment Div (USA)
FFB571TYPEA2CLASSC Federal Specifications Promulgated by General Services Administration Washington DC (USA)
Related Parts
5310-00-265-9217INTERCHANGEABLE
NUT,PLAIN,HEXAGON
5310-00-265-9221INTERCHANGEABLE
NUT,PLAIN,HEXAGON
5310-00-265-9222INTERCHANGEABLE
NUT,PLAIN,HEXAGON
5310-00-266-0379INTERCHANGEABLE
NUT,PLAIN,HEXAGON
5310-00-266-0380INTERCHANGEABLE
NUT,PLAIN,HEXAGON

Frequently Asked Questions

What is NSN 5310-00-266-0377?

NSN 5310-00-266-0377 is a Nut,plain,hexagon, manufactured by Navistar Intl Corp Melrose Park Engine Plant Location /melrose Park/, classified under FSC 5310 (No Item Name Available). Status: active.

What are the part numbers for NSN 5310-00-266-0377?

NSN 5310-00-266-0377 has 4 cross-referenced part numbers: 18277R1 (Navistar Intl Corp Melrose Park Engine Plant Location /melrose Park/), 18277R1 (Navistar International Corporation Dba Navistar), 18277R1 (International Harvester Co Agricultural Equipment Div), FFB571TYPEA2CLASSC (Federal Specifications Promulgated by General Services Administration Washington DC).

What NSN replaces 5310-00-266-0377?

There are 5 known substitutes for 5310-00-266-0377: 5310-00-265-9217, 5310-00-265-9221, 5310-00-265-9222 and 2 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 18277R1?

Key specifications for 18277R1: Thread Direction: LEFT-HAND; Bearing Surface Type: WASHER FACED; Thread Quantity Per Inch: 13; Thread Series: UNIFIED NATIONAL COARSE (UNC). 11 total characteristics are documented in the Federal Logistics Information System.

Validated with multiple authoritative sources, including Government, OEM, and Certified sources.
PartsTable Design LLC · partstable.com