PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

261012Bolt,externally Relieved Body

Rtx Corporation Dba Pratt & Whitney Div Pratt &whitney · NSN 5306-00-637-8688 · FSC 5306 · No Item Name Available
Verified by PartsTable
NSN 5306-00-637-8688 — this item is cataloged by the U.S. Government under National Stock Number 5306-00-637-8688. Primary manufacturer part number: 261012.
Features
  • Bolt,externally Relieved Body — FSC 5306
  • Head Height: 0.320 INCHES MINIMUM AND 0.340 INCHES MAXIMUM IN
  • Thread Direction: RIGHT-HAND
  • Extended Washer Diameter: 0.428 INCHES MINIMUM AND 0.448 INCHES MAXIMUM IN
  • Surface Treatment Document and Classification: AMS 2416 ASSN STD ALL TREATMENT RESPONSES OVERALL
  • Material Document and Classification: AMS 6304 ASSN STD SINGLE MATERIAL RESPONSE OVERALL
  • Externally Relieved Body Diameter Quantity: 1
  • Surface Treatment: NICKEL AND CADMIUM OVERALL
Applications
  • Structural fastening and assembly
  • Equipment mounting
  • Panel and housing attachment
  • Applications requiring Steel Comp 601 Overall construction
General Description

The Bolt,externally Relieved Body, cataloged under National Stock Number 5306-00-637-8688, is classified within Federal Supply Class 5306 (No Item Name Available) of the Hardware and Abrasives group. The primary manufacturer of record is Rtx Corporation Dba Pratt & Whitney Div Pratt &whitney. Government technical data includes 24 verified specifications, sourced from the Federal Logistics Information System (FLIS). This item has 1 commercial cross-reference from 1 manufacturer, 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
NSN5306-00-637-8688
Primary Part Number261012
Item NameBolt,externally Relieved Body
FSC / FSG5306 / 53 — No Item Name Available
ManufacturerRtx Corporation Dba Pratt & Whitney Div Pratt &whitney
StatusCANCELLED
Head Height0.320 INCHES MINIMUM AND 0.340 INCHES MAXIMUM IN
Thread DirectionRIGHT-HAND
Extended Washer Diameter0.428 INCHES MINIMUM AND 0.448 INCHES MAXIMUM IN
Surface Treatment Document and ClassificationAMS 2416 ASSN STD ALL TREATMENT RESPONSES OVERALL
Material Document and ClassificationAMS 6304 ASSN STD SINGLE MATERIAL RESPONSE OVERALL
Externally Relieved Body Diameter Quantity1
Surface TreatmentNICKEL AND CADMIUM OVERALL
Hardness Rating30.0 ROCKWELL C MINIMUM AND 38.0 ROCKWELL C MAXIMUM OVERALL
Hole Configuration StyleHEXAGON LONGITUDINAL HOLE
Thread Series DesignatorUNIFIED NATIONAL COARSE (UNC)
MaterialSTEEL COMP 601 OVERALL
Nonstandard Thread Pitch Diameter+0.2216 TO 0.2238 INCHES IN
Hole Quantity4
Fastener Length1.678 INCHES MINIMUM AND 1.698 INCHES MAXIMUM IN
Hole Diameter0.062 INCHES NOMINAL IN
Thread Length0.730 INCHES MINIMUM AND 0.770 INCHES MAXIMUM IN
Hole TypeDRILLED
Nominal Thread Diameter0.250 INCHES IN
Head StyleDOUBLE HEXAGON W/HOLE
First Diameter From Head0.218 INCHES MINIMUM AND 0.228 INCHES MAXIMUM IN
Thread Quantity Per Inch28
Width Between Flats0.304 INCHES MINIMUM AND 0.313 INCHES MAXIMUM IN
Distance From Largest Bearing Surface of Head to End of First Diameter0.928 INCHES MINIMUM AND 0.948 INCHES MAXIMUM IN
Extended Washer Thickness0.060 INCHES MINIMUM AND 0.070 INCHES MAXIMUM IN
Lifecycle & Compliance
Acquisition StatusCANCELLED
HAZMATNo
Verified Substitutes 2
No Item Name Available
5210-00-600-5757C331-300 INTERCHANGEABLE
Rule,machinist's
L.s. Starrett Company (the) Div Tool Division
Cross-Reference Index
Part NumberManufacturer
261012 PRIMARY Rtx Corporation Dba Pratt & Whitney Div Pratt &whitney (USA)
Related Parts
5306-00-638-3799SUCCESSOR
NO ITEM NAME AVAILABLE
5210-00-600-5757INTERCHANGEABLE
RULE,MACHINIST'S
C331-300

Frequently Asked Questions

What is NSN 5306-00-637-8688?

NSN 5306-00-637-8688 is a Bolt,externally Relieved Body, manufactured by Rtx Corporation Dba Pratt & Whitney Div Pratt &whitney, classified under FSC 5306 (No Item Name Available). Status: cancelled.

What are the part numbers for NSN 5306-00-637-8688?

NSN 5306-00-637-8688 has 1 cross-referenced part number: 261012 (Rtx Corporation Dba Pratt & Whitney Div Pratt &whitney).

What NSN replaces 5306-00-637-8688?

There are 2 known substitutes for 5306-00-637-8688: 5306-00-638-3799, 5210-00-600-5757. Verify interchangeability with system specifications before substitution.

What are the specifications of 261012?

Key specifications for 261012: Head Height: 0.320 INCHES MINIMUM AND 0.340 INCHES MAXIMUM IN; Thread Direction: RIGHT-HAND; Extended Washer Diameter: 0.428 INCHES MINIMUM AND 0.448 INCHES MAXIMUM IN; Surface Treatment Document and Classification: AMS 2416 ASSN STD ALL TREATMENT RESPONSES OVERALL. 24 total characteristics are documented in the Federal Logistics Information System.

Is NSN 5306-00-637-8688 still in active supply?

NSN 5306-00-637-8688 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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