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MS21289-12
Military Standard Bolt
Description
Fastener Length: 7/8", Hole Diameter: 5/64", Thread: 1/4-28, Thread Length: 3/4"
Specifications
| Extended Washer Diameter | 0.428 inches minimum and 0.448 inches maximum |
|---|---|
| Extended Washer Thickness | 0.060 inches minimum and 0.070 inches maximum |
| Fastener Length | 0.865 inches minimum and 0.885 inches maximum |
| Features Provided | Finished head |
| Hardness Rating | 24.0 rockwell c minimum and 28.0 rockwell c maximum |
| Head Height | 0.320 inches minimum and 0.340 inches maximum |
| Head Style | Double hexagon w/hole |
| Hole Configuration Style | Double hexagon longitudinal hole |
| Hole Diameter | 0.070 |
| Hole Quantity | 4 |
| Hole Type | Drilled |
| Length | 7/8 |
| Material | Iron |
| Material Specification | Ams5732 assn std single material response |
| Min. Tensile Strength (psi) | 130000 pounds per square inch |
| Minimum Yield Strength | 85000 pounds per square inch |
| Surface Finish | 32.0 microinches threads, 63.0 microinches bearing surface of head, 63.0 microinches grip |
| Thread Class | 3a |
| Thread Diameter | 0.250 |
| Thread Direction | Right-hand |
| Thread Length | 0.740 inches minimum and 0.820 inches maximum |
| Thread Qty | 28 |
| Thread Qty Per Inch (tpi) | 28 |
| Thread Series Designator | UNJF |
| Thread Size | 1/4 |
| Width Between Flats | 0.304 inches minimum and 0.313 inches maximum |
Other sizes
Parts that share this base number, ordered by size. Always verify the full specification before substituting.
- MS21289-05
- MS21289-08
- MS21289-10
- MS21289-12
- MS21289-23
- MS21289-24
- MS21289-27
Cross-reference
No interchangeable or dimensionally similar parts are on record for MS21289-12. Try the cross-reference lookup to search by a different part number.
Catalog data updated 2026-07-05. Report a data error