The Washer,flat, cataloged under National Stock Number 5310-01-482-5057, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Mcmaster-Carr Supply Co. Government technical data includes 10 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-01-482-5057 |
| Primary Part Number | 98019A300 |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Mcmaster-Carr Supply Co |
| Status | ACTIVE |
| Overall Diameter | 0.250 INCHES NOMINAL IN |
| Hardness Rating | 70.0 ROCKWELL B NOMINAL |
| Material Document and Classification | MS15795 MIL SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Cross-Sectional Shape Style | RECTANGULAR |
| Surface Treatment | PASSIVATE OVERALL |
| Peripheral Shape Style | ROUND |
| Material | STEEL CORROSION RESISTING OVERALL |
| Center Hole Shape Style | ROUND |
| Hole Diameter | 0.094 INCHES NOMINAL IN |
| Thickness | 0.016 INCHES MINIMUM AND 0.025 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 |
| Part Number | Manufacturer |
|---|---|
| 98019A300 PRIMARY | Mcmaster-Carr Supply Co (USA) |
| Reference | Meaning |
|---|---|
| 98019A100 | 5/9 Secondary reference Mcmaster-Carr Supply Co |
NSN 5310-01-482-5057 is a Washer,flat, manufactured by Mcmaster-Carr Supply Co, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-482-5057 has 1 manufacturer part number on file: 98019A300 (Mcmaster-Carr Supply Co).
Key specifications for 98019A300: Overall Diameter: 0.250 INCHES NOMINAL IN; Hardness Rating: 70.0 ROCKWELL B NOMINAL; Material Document and Classification: MS15795 MIL SPEC SINGLE 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.