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MS21921-4D
Military Standard Tube Coupling Nut
Description
Nut
Specifications
| Criticality Code Justification | Feat |
|---|---|
| Diameter C Tolerance | -000 in |
| Dimension A | 0.72 in |
| Dimension A Tolerance | +0.010 in |
| Dimension B | 0.18 in |
| Dimension B Tolerance | +0.010 in |
| Dimension C | 0.552 in |
| Dimension H | 0.562 in |
| End Application | E-3a aircraft warning and control system (awacs) starlifter c-141 aircraft f-111. tomcat f-14a delta dart f-106 chinook ch-47 helicopter iroquis uh-1 aircraft application |
| Industry Standards/Certification | MIL-S-8879 |
| Material | Aluminum |
| Material Specification | T62 or t851 federal specification single material response t6 t6 federal specification single material response or qq-a-225/6 qq-a-367 |
| NIIN | 00-555-8203 |
| NSN | 4730-00-555-8203 |
| Nut Height | Between 0.710 inches and 0.730 inches |
| Nut Style | Tube coupling |
| Seat Angle | 45.00 degrees |
| Special Features | Grumman aerospace corporation a10 aircraft; weapon system essential |
| Specification Data | 96906-ms21921 government standard |
| Surface Treatment | Anodize |
| Surface Treatment Specification | Class 1 military specification single treatment response type 2 mil-a-8625 |
| Thread Class | 3b |
| Thread Direction | Right-hand |
| Thread Qty | 20 |
| Thread Qty Per Inch (tpi) | 20 |
| Thread Series | Unjf (fine thread with external controlled root radius) |
| Thread Size | 0.438 |
| Thread T (MIL-S-8879) | 0.4375-20 |
| Tube Outside Diameter | 1/4 in |
| Weight | 0.03 lb |
| Width Across Flats | 0.562 |
Cross-reference
Similar parts
Parts with matching key dimensions — often from a different standards family. Candidates for comparison only; verify the full specification before substituting.
- MS21921-4 MS 7/16-20 · Steel
- MS21921-4J MS 7/16-20 · CRES
- MS21921V4P MS 7/16-20 · Steel
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Catalog data updated 2026-07-05. Report a data error