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MS21921-8D
Military Standard Tube Coupling Nut
Description
Nut
Specifications
| Alternate Part Number | MS21921-8W |
|---|---|
| Diameter C Tolerance | -000 in |
| Dimension A | 0.86 in |
| Dimension A Tolerance | +0.010 in |
| Dimension B | 0.18 in |
| Dimension B Tolerance | +0.010 in |
| Dimension C | 0.865 in |
| Dimension H | 7/8 in |
| Industry Standards/Certification | MIL-S-8879 |
| Material | Aluminum |
| NIIN | 01-087-7557 |
| NSN | 4730-01-087-7557 |
| Nut Height | Between 0.850 inches and 0.870 inches |
| Nut Style | Tube coupling |
| Seat Angle | 45.0 degrees |
| Specification Data | 96906-ms21921 government standard |
| Thread Class | 3b |
| Thread Direction | Right-hand |
| Thread Qty | 16 |
| Thread Qty Per Inch (tpi) | 16 |
| Thread Series | Unjf (fine thread with external controlled root radius) |
| Thread Size | 0.750 |
| Thread T (MIL-S-8879) | 0.7500-16 |
| Tube Outside Diameter | 1/2 in |
| Weight | 0.025 lb |
| Width Across Flats | Between 0.871 inches and 0.875 inches |
Cross-reference
Interchangeable
Parts that share a National Stock Number or are listed as an alternate for MS21921-8D — functionally equivalent.
- MS21921-8W Listed alternate 3/4-16 · Aluminum
Similar parts
Parts with matching key dimensions — often from a different standards family. Candidates for comparison only; verify the full specification before substituting.
- MS21921-8 MS 3/4-16 · Steel
- MS21921-8J MS 3/4-16 · CRES
- MS21921-8K MS 3/4-16 · CRES
- MS21921V8P MS 3/4-16 · CRES
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Catalog data updated 2026-07-05. Report a data error