The Washer,flat, cataloged under National Stock Number 5310-00-381-1637, 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10 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-00-381-1637 |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Status | ACTIVE |
| Surface Treatment Document and Classification | MIL-A-8625 MIL SPEC SINGLE TREATMENT RESPONSE OVERALL |
| Overall Diameter | 0.428 INCHES MINIMUM AND 0.448 INCHES MAXIMUM IN |
| Material Document and Classification | QQ-A-250/4,T3,T4 OR T351 FED SPEC 1ST MATERIAL RESPONSE OR QQ-A-200/3,T3,T3510 OR T3511 FED SPEC 2ND MATERIAL RESPONSE OVERALL |
| Cross-Sectional Shape Style | RECTANGULAR |
| Surface Treatment | ANODIZE OVERALL |
| Peripheral Shape Style | ROUND |
| Material | ALUMINUM ALLOY 2024 OVERALL |
| Center Hole Shape Style | ROUND |
| Hole Diameter | 0.255 INCHES MINIMUM AND 0.265 INCHES MAXIMUM IN |
| Thickness | 0.060 INCHES MINIMUM AND 0.066 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 |
|---|---|
| 140-019-1 | 3/2 Design control — primary reference U.S. Government activity |
NSN 5310-00-381-1637 is a Washer,flat, classified under FSC 5310, Nuts and Washers. Status: active.
Key specifications for 5310-00-381-1637: Surface Treatment Document and Classification: MIL-A-8625 MIL SPEC SINGLE TREATMENT RESPONSE OVERALL; Overall Diameter: 0.428 INCHES MINIMUM AND 0.448 INCHES MAXIMUM IN; Material Document and Classification: QQ-A-250/4,T3,T4 OR T351 FED SPEC 1ST MATERIAL RESPONSE OR QQ-A-200/3,T3,T3510 OR T3511 FED SPEC 2ND MATERIAL RESPONSE OVERALL; Cross-Sectional Shape Style: RECTANGULAR. 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.