PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

21251Setscrew

Erie Strayer Co · NSN 5305-01-158-6765 · FSC 5305 · No Item Name Available
Verified by PartsTable
NSN 5305-01-158-6765 — this item is cataloged by the U.S. Government under National Stock Number 5305-01-158-6765. Primary manufacturer part number: 21251.
Features
  • Setscrew — FSC 5305
  • Thread Direction: RIGHT-HAND
  • Thread Class: 2A A
  • Nominal Thread Diameter: 1.125 INCHES IN
  • Internal Drive Style: W/O INTERNAL DRIVE
  • Head Style: FLAT COUNTERSUNK
  • Thread Quantity Per Inch: 7
  • Point Style: OVAL
Applications
  • Applications requiring Steel Comp 4140 Overall construction
General Description

The Setscrew, cataloged under National Stock Number 5305-01-158-6765, is classified within Federal Supply Class 5305 (No Item Name Available) of the Hardware and Abrasives group. The primary manufacturer of record is Erie Strayer Co. Government technical data includes 13 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 2 commercial cross-references from 1 manufacturer, enabling identification through both NSN and commercial part number lookups. 10 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN5305-01-158-6765
Primary Part Number21251
Item NameSetscrew
FSC / FSG5305 / 53 — No Item Name Available
ManufacturerErie Strayer Co
StatusACTIVE
Thread DirectionRIGHT-HAND
Thread Class2A A
Nominal Thread Diameter1.125 INCHES IN
Internal Drive StyleW/O INTERNAL DRIVE
Head StyleFLAT COUNTERSUNK
Thread Quantity Per Inch7
Point StyleOVAL
Fastener Length5.000 INCHES NOMINAL IN
Head Diameter2.031 INCHES NOMINAL IN
Countersink Angle78.0 DEGREES NOMINAL
Material Document and ClassificationSAE ASSN STD SINGLE MATERIAL RESPONSE OVERALL
Thread Series DesignatorUNIFIED NATIONAL COARSE (UNC)
MaterialSTEEL COMP 4140 OVERALL
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 10
5110-00-255-6557 INTERCHANGEABLE
Reamer,hand
5985-00-399-7135ESD3362-4 INTERCHANGEABLE
Mast Section
Us Army Communications & Electronics Materiel Readiness Command Logistics Engineering Dir
5310-00-685-161821251 INTERCHANGEABLE
Washer,finishing
Mason Electric Co. Dba Mason Controls
1660-00-881-030621251 INTERCHANGEABLE
Converter,liquid Oxygen
Ingersoll-Rand Company Dba Ingersoll-Rand
1660-00-912-327521251-1 INTERCHANGEABLE
Converter,liquid Oxygen
Mission Systems Orchard Park Inc
4520-01-020-3263 INTERCHANGEABLE
Heating Element,electrical,nonim
2910-01-168-8088J8123050 INTERCHANGEABLE
Float,carburetor
Chrysler Corp Engine and Components Sales Diversified Products Div
4730-01-231-862121251 INTERCHANGEABLE
Adapter,straight,tube to Boss
Stanadyne Corporation Dba Stanadyne Diesel Systems Div Diesel Systems
5305-01-298-062921251 INTERCHANGEABLE
Screw,cap,hexagon Head
Industrial Technologies and Services Llc
6105-01-300-647221251-2 INTERCHANGEABLE
Motor,alternating Current
Silver King Refrigeration Inc.
Cross-Reference Index
Part NumberManufacturer
21251-1 Erie Strayer Co (USA)
21251 PRIMARY Erie Strayer Co (USA)
Related Parts
5110-00-255-6557INTERCHANGEABLE
REAMER,HAND
5985-00-399-7135INTERCHANGEABLE
MAST SECTION
ESD3362-4
5310-00-685-1618INTERCHANGEABLE
WASHER,FINISHING
21251
1660-00-881-0306INTERCHANGEABLE
CONVERTER,LIQUID OXYGEN
21251
1660-00-912-3275INTERCHANGEABLE
CONVERTER,LIQUID OXYGEN
21251-1
4520-01-020-3263INTERCHANGEABLE
HEATING ELEMENT,ELECTRICAL,NONIM
2910-01-168-8088INTERCHANGEABLE
FLOAT,CARBURETOR
J8123050
4730-01-231-8621INTERCHANGEABLE
ADAPTER,STRAIGHT,TUBE TO BOSS
21251
5305-01-298-0629INTERCHANGEABLE
SCREW,CAP,HEXAGON HEAD
21251
6105-01-300-6472INTERCHANGEABLE
MOTOR,ALTERNATING CURRENT
21251-2

Frequently Asked Questions

What is NSN 5305-01-158-6765?

NSN 5305-01-158-6765 is a Setscrew, manufactured by Erie Strayer Co, classified under FSC 5305 (No Item Name Available). Status: active.

What are the part numbers for NSN 5305-01-158-6765?

NSN 5305-01-158-6765 has 2 cross-referenced part numbers: 21251-1 (Erie Strayer Co), 21251 (Erie Strayer Co).

What NSN replaces 5305-01-158-6765?

There are 10 known substitutes for 5305-01-158-6765: 5110-00-255-6557, 5985-00-399-7135, 5310-00-685-1618 and 7 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 21251?

Key specifications for 21251: Special Features: ONE DRILLED SLOT ON SIDE OF HEAD,0.188 INCH NOMINAL IN WIDTH IN; Thread Direction: RIGHT-HAND; Thread Class: 2A A; Nominal Thread Diameter: 1.125 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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