The Nut,self-Locking,extended Washer, cataloged under National Stock Number 5310-01-644-0424, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. Government technical data includes 12 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-01-644-0424 |
| Item Name | Nut,self-Locking,extended Washer |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Status | ACTIVE |
| Washer Outside Diameter | 0.420 INCHES MAXIMUM IN |
| Width Across Flats | 0.304 INCHES MINIMUM AND 0.316 INCHES MAXIMUM IN |
| Thread Series | UNIFIED NATIONAL JOINT FINE (UNJF) |
| Washer Thickness | 0.019 INCHES MINIMUM IN |
| Thread Direction | RIGHT-HAND |
| Nominal Thread Size | 0.250 INCHES IN |
| Locking Feature | PREVAILING TORQUE ALL METAL DESIGN |
| Surface Treatment | CADMIUM AND CHROMATE OVERALL |
| Nut Style | HEXAGON |
| Thread Class | 3B |
| Thread Quantity Per Inch | 28 |
| Material | STEEL OVERALL |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| NASM21042-C420A | 2/2 Government specification standardization U.S. Government activity |
| MS20365-C420A | 5/9 Secondary reference U.S. Government activity |
NSN 5310-01-644-0424 is a Nut,self-Locking,extended Washer, classified under FSC 5310, Nuts and Washers. Status: active.
Key specifications for 5310-01-644-0424: Overall Height: 0.204 INCHES MINIMUM AND 0.219 INCHES MAXIMUM IN; Washer Outside Diameter: 0.420 INCHES MAXIMUM IN; Width Across Flats: 0.304 INCHES MINIMUM AND 0.316 INCHES MAXIMUM IN; Thread Series: UNIFIED NATIONAL JOINT FINE (UNJF). 12 specifications are documented in the U.S. Government catalog.
No hazard code in the DLA record (HMIC N). Hazard information on this page is shown exactly as it appears in the DLA record.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-16.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.