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MS9557-34
Military Standard Machine Bolt
Description
Fastener Length: 2-3/4", Thread: 1/4-28, Thread Length: 51/64
Specifications
| Extended Washer Diameter | 0.438 |
|---|---|
| Extended Washer Thickness | 0.060 |
| Fastener Length | 2.750 |
| Features Provided | Finished head |
| Grip Length | Between 1.940 inches and 2.000 inches |
| Hardness Rating | 24.0 rockwell c and 35.0 rockwell c |
| Head Height | 0.300 |
| Head Style | Double hexagon w/hole |
| Length | 2 3/4 |
| Material | Iron |
| Material Specification | Ams 5731 assn standard 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 bearing surface of head, 32.0 microinches grip, 32.0 microinches threads |
| Thread Class | 3a |
| Thread Diameter | 0.250 |
| Thread Direction | Right-hand |
| Thread Length | Between 0.750 inches and 0.810 inches |
| Thread Qty | 28 |
| Thread Qty Per Inch (tpi) | 28 |
| Thread Series | UNJF |
| Thread Series Designator | Unjf (fine thread with external controlled root radius) |
| Thread Size | 1/4 |
| Width Between Flats | 0.312 |
Cross-reference
No interchangeable or dimensionally similar parts are on record for MS9557-34. Try the cross-reference lookup to search by a different part number.
Catalog data updated 2026-07-05. Report a data error