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MS21244-4
Military Standard Plain Castellated Hexagon Nut
Description
Assembled washer, 1/4-28 unjf thread, A grade steel, MS21244 series nut
Specifications
| Bearing Surface Finish | 125.0 microinches |
|---|---|
| Counterbore Diameter | 0.299 inches minimum nut and 0.309 inches maximum nut |
| Material | CRES |
| Nondefinitive Specification/Std Data | A grade |
| Nut Counterbore Depth | 0.172 inches minimum nut and 0.192 inches maximum nut |
| Nut Style | Flat with turned back edge |
| Overall Height | 0.365 inches minimum and 0.405 inches maximum |
| Surface Treatment | Cadmium and chromate, Passivate |
| Surface Treatment Specification | Qq-p-35 fed spec single treatment response washer, Qq-p-416 type 2 class 2 fed spec single treatment response nut |
| Temperature Rating | 450.0 deg fahrenheit maximum |
| Thread Class | 3b |
| Thread Direction | Right-hand |
| Thread Qty | 28 |
| Thread Qty Per Inch (tpi) | 28 |
| Thread Series | UNJF |
| Thread Size | 0.250 |
| Washer Outside Diameter | 0.530 inches minimum and 0.560 inches maximum |
| Width Across Flats | 0.430 inches minimum and 0.439 inches maximum |
Other sizes
Parts that share this base number, ordered by size. Always verify the full specification before substituting.
- MS21244-4
- MS21244-10
Cross-reference
No interchangeable or dimensionally similar parts are on record for MS21244-4. Try the cross-reference lookup to search by a different part number.
Catalog data updated 2026-07-05. Report a data error