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MS9557-12
Military Standard Machine Bolt
Description
Fastener Length: 7/8", Thread: 1/4-28, Thread Length: 51/64", MS9557 series bolt
Specifications
| Country of Origin | USA |
|---|---|
| Extended Washer Diameter | 0.438 |
| Extended Washer Thickness | 0.060 |
| Fastener Length | 0.865 inches minimum and 0.885 inches maximum |
| Features Provided | Finished head |
| Grip Length | 0.079 inches minimum and 0.125 inches maximum |
| Head Height | 0.300 |
| Head Style | Double hexagon extended washer |
| Length | 7/8 |
| Material | Iron |
| Material Specification | Ams 5731 assn std single material response |
| 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 | 0.740 inches minimum and 0.806 inches maximum |
| Thread Qty | 28 |
| Thread Qty Per Inch (tpi) | 28 |
| Thread Series Designator | UNJF |
| Thread Size | 1/4 |
| Weight | .005 lb |
| Width Between Flats | 0.312 |
Cross-reference
No interchangeable or dimensionally similar parts are on record for MS9557-12. Try the cross-reference lookup to search by a different part number.
Catalog data updated 2026-07-05. Report a data error