bolts › machine bolts
MS9558-12
Military Standard Machine Bolt
Description
Length: 0-63/64", Thread: 1/4-24, Thread Length: 59/64", MS9558 series bolt
Specifications
| Extended Washer Diameter | Between 0.490 inches and 0.510 inches |
|---|---|
| Extended Washer Thickness | 0.070 |
| Fastener Length | Between 0.990 inches and 1.010 inches |
| Features Provided | Finished head |
| Grip Length | Between 0.088 inches and 0.125 inches |
| Head Height | Between 0.338 inches and 0.358 inches |
| Head Style | Double hexagon extended washer |
| Material | Iron |
| Material Specification | Ams 5731 assn standard single material response |
| Surface Finish | 32.0 microinches bearing surface of head, 32.0 microinches threads |
| Thread Class | 3a |
| Thread Diameter | 0.312 |
| Thread Direction | Right-hand |
| Thread Length | Between 0.865 inches and 0.922 inches |
| Thread Qty | 24 |
| Thread Qty Per Inch (tpi) | 24 |
| Thread Series | UNJF |
| Thread Series Designator | Unjf (fine thread with external controlled root radius) |
| Thread Size | 1/4 |
| Width Between Flats | Between 0.365 inches and 0.385 inches |
Other sizes
Parts that share this base number, ordered by size. Always verify the full specification before substituting.
Cross-reference
No interchangeable or dimensionally similar parts are on record for MS9558-12. Try the cross-reference lookup to search by a different part number.
Catalog data updated 2026-07-05. Report a data error