PartsTable TECHNICAL DATA SHEET
JULY 2026Technical Data Sheet

21637Spring,helical,extension

Optical Technology Devices Inc · NSN 5360-00-597-2191 · FSC 5360 · No Item Name Available
Verified by PartsTable
NSN 5360-00-597-2191 — this item is cataloged by the U.S. Government under National Stock Number 5360-00-597-2191. Primary manufacturer part number: 21637.
Features
  • Spring,helical,extension — FSC 5360
  • Hook Radius: 0.127 INCHES NOMINAL BOTH ENDS IN
  • Opening Width: 0.062 INCHES NOMINAL BOTH ENDS IN
  • Material: STEEL OVERALL
  • Spring Free Length: 0.870 INCHES NOMINAL IN
  • End Style: MACHINED HALF LOOP BOTH ENDS
  • Coil Quantity: 22
  • Style Designator: CYLINDRICAL
Applications
  • Mechanical energy storage
  • Vibration dampening
  • Return mechanism operation
  • Applications requiring Steel Overall construction
General Description

The Spring,helical,extension, cataloged under National Stock Number 5360-00-597-2191, is classified within Federal Supply Class 5360 (No Item Name Available) of the Hardware and Abrasives group. The primary manufacturer of record is Optical Technology Devices Inc. Government technical data includes 12 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. 4 verified substitutes exist in the FLIS interchangeability database. Current acquisition status: Active.

Technical Specifications
ParameterValue
NSN5360-00-597-2191
Primary Part Number21637
Item NameSpring,helical,extension
FSC / FSG5360 / 53 — No Item Name Available
ManufacturerOptical Technology Devices Inc
StatusACTIVE
Hook Radius0.127 INCHES NOMINAL BOTH ENDS IN
Opening Width0.062 INCHES NOMINAL BOTH ENDS IN
MaterialSTEEL OVERALL
Spring Free Length0.870 INCHES NOMINAL IN
End StyleMACHINED HALF LOOP BOTH ENDS
Coil Quantity22
Style DesignatorCYLINDRICAL
Design TypeCLOSED
Material Document and ClassificationQQ-W-423,FORM 1,COND B FED SPEC ALL MATERIAL RESPONSES OVERALL
Inside Diameter0.178 INCHES NOMINAL IN
Coil Helix DirectionRIGHT-HAND
Spring Free Outside Diameter0.214 INCHES NOMINAL IN
Lifecycle & Compliance
Acquisition StatusACTIVE
HAZMATNo
Verified Substitutes 4
5950-00-019-150421637 INTERCHANGEABLE
Core,electromagnetic Component
Hamilton Sundstrand Corporation Dba Collins Aerospace
2520-00-759-4741ETN0021637 INTERCHANGEABLE
Differential Bearin
Navistar Intl Corp Truck Br Ohio Plant
5915-01-329-786210073-7314 INTERCHANGEABLE
Filter,band Pass
L3harris Technologies, Inc. Dba Harris Corp Div Harris Defense Communications
5945-01-439-689321637 INTERCHANGEABLE
Relay,electromagnetic
Hf Scientific Inc.
Cross-Reference Index
Part NumberManufacturer
21637 Optical Technology Devices Inc (USA)
Related Parts
5950-00-019-1504INTERCHANGEABLE
CORE,ELECTROMAGNETIC COMPONENT
21637
2520-00-759-4741INTERCHANGEABLE
DIFFERENTIAL BEARIN
ETN0021637
5915-01-329-7862INTERCHANGEABLE
FILTER,BAND PASS
10073-7314
5945-01-439-6893INTERCHANGEABLE
RELAY,ELECTROMAGNETIC
21637

Frequently Asked Questions

What is NSN 5360-00-597-2191?

NSN 5360-00-597-2191 is a Spring,helical,extension, manufactured by Optical Technology Devices Inc, classified under FSC 5360 (No Item Name Available). Status: active.

What are the part numbers for NSN 5360-00-597-2191?

NSN 5360-00-597-2191 has 1 cross-referenced part number: 21637 (Optical Technology Devices Inc).

What NSN replaces 5360-00-597-2191?

There are 4 known substitutes for 5360-00-597-2191: 5950-00-019-1504, 2520-00-759-4741, 5915-01-329-7862 and 1 more. Verify interchangeability with system specifications before substitution.

What are the specifications of 21637?

Key specifications for 21637: Hook Radius: 0.127 INCHES NOMINAL BOTH ENDS IN; Opening Width: 0.062 INCHES NOMINAL BOTH ENDS IN; Material: STEEL OVERALL; Spring Free Length: 0.870 INCHES NOMINAL IN. 12 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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