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MS21921-6W
Military Standard Tube Coupling Nut
Description
Nut
Specifications
| Diameter C Tolerance | -000 in |
|---|---|
| Dimension A | 0.80 in |
| Dimension A Tolerance | +0.010 in |
| Dimension B | 0.18 in |
| Dimension B Tolerance | +0.010 in |
| Dimension C | 0.677 in |
| Dimension H | 0.688 in |
| End Application | Aircraft application |
| Industry Standards/Certification | MIL-S-8879 |
| Material | Aluminum |
| Material Specification | T6 federal specification single material response qq-a-225/6 |
| NIIN | 00-491-9564 |
| NSN | 4730-00-491-9564 |
| Nut Height | 0.800 |
| Nut Style | Tube coupling |
| Seat Angle | 45.00 degrees |
| Specification Data | 81343-as21921 professional/industrial association specification |
| Surface Treatment | Anodize |
| Thread Class | 3b |
| Thread Direction | Right-hand |
| Thread Qty Per Inch (tpi) | 18 |
| Thread Series | Unf (fine thread) |
| Thread Size | 0.562 |
| Thread T (MIL-S-8879) | 0.5625-18 |
| Tube Outside Diameter | 3/8 in |
| Weight | .005 lb |
| Width Across Flats | 0.688 |
Cross-reference
Interchangeable
Parts that share a National Stock Number or are listed as an alternate for MS21921-6W — functionally equivalent.
- MS21921-6D Listed alternate 9/16-18 · Aluminum
Similar parts
Parts with matching key dimensions — often from a different standards family. Candidates for comparison only; verify the full specification before substituting.
- MS21921-6 MS 9/16-18 · CRES
- MS21921-6J MS 9/16-18 · CRES
Looking for a specific part? Use the cross-reference lookup.
Catalog data updated 2026-07-05. Report a data error