The Washer,flat, cataloged under National Stock Number 5310-01-421-4256, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. Government technical data includes 10 specifications, cited from the U.S. Government catalog. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-01-421-4256 |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Status | ACTIVE |
| Surface Treatment Document and Classification | QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Overall Diameter | 1.057 INCHES MINIMUM AND 1.062 INCHES MAXIMUM IN |
| Cross-Sectional Shape Style | RECTANGULAR |
| Specification/standard Data | 80205-NAS1149 PROFESSIONAL/INDUSTRIAL ASSOCIATION STANDARD |
| Surface Treatment | PASSIVATE OVERALL |
| Peripheral Shape Style | ROUND |
| Material | STEEL COMP 301 OR STEEL COMP 302 OR STEEL COMP 304 OR STEEL COMP 316 OR STEEL COMP 321 OR STEEL COMP 347 OVERALL |
| Center Hole Shape Style | ROUND |
| Hole Diameter | 0.573 INCHES MINIMUM AND 0.578 INCHES MAXIMUM IN |
| Thickness | 0.028 INCHES MINIMUM AND 0.036 INCHES MAXIMUM IN |
| 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 |
|---|---|
| NAS1149C0932R | 5/2 Secondary reference U.S. Government activity |
| NAS1149C0932R | 3/2 Design control — primary reference U.S. Government activity |
| 5310PL1474705 | 6/9 Informative reference only Jednolity Indeks Materialowy - Uniform Material Index |
NSN 5310-01-421-4256 is a Washer,flat, classified under FSC 5310, Nuts and Washers. Status: active.
1 possible match (shared part number, not a government interchangeability claim): 5310-01-497-3985. Verify interchangeability with system specifications before substitution.
Key specifications for 5310-01-421-4256: Surface Treatment Document and Classification: QQ-P-35 FED SPEC SINGLE TREATMENT RESPONSE OVERALL; Overall Diameter: 1.057 INCHES MINIMUM AND 1.062 INCHES MAXIMUM IN; Cross-Sectional Shape Style: RECTANGULAR; Specification/standard Data: 80205-NAS1149 PROFESSIONAL/INDUSTRIAL ASSOCIATION STANDARD. 10 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.