The Washer,flat, cataloged under National Stock Number 5310-00-487-7861, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Lockheed Martin Corporation Div Rms - Mitchel Field. Government technical data includes 8 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. 3 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-00-487-7861 |
| Primary Part Number | 249971 |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Lockheed Martin Corporation Div Rms - Mitchel Field |
| Status | ACTIVE |
| Overall Diameter | 0.500 INCHES NOMINAL IN |
| Material Document and Classification | QQ-L-201 GRADE B FED SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Cross-Sectional Shape Style | RECTANGULAR |
| Peripheral Shape Style | ROUND |
| Material | LEAD OVERALL |
| Center Hole Shape Style | ROUND |
| Hole Diameter | 0.140 INCHES NOMINAL IN |
| Thickness | 0.031 INCHES NOMINAL 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 |
|---|---|
| 249971 PRIMARY | Lockheed Martin Corporation Div Rms - Mitchel Field (USA) |
NSN 5310-00-487-7861 is a Washer,flat, manufactured by Lockheed Martin Corporation Div Rms - Mitchel Field, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-00-487-7861 has 1 manufacturer part number on file: 249971 (Lockheed Martin Corporation Div Rms - Mitchel Field).
3 possible matches (shared part number, not a government interchangeability claim): 5340-01-353-5267, 4820-01-524-0270, 5930-01-667-4818. Verify interchangeability with system specifications before substitution.
Key specifications for 249971: Overall Diameter: 0.500 INCHES NOMINAL IN; Material Document and Classification: QQ-L-201 GRADE B FED SPEC SINGLE MATERIAL RESPONSE OVERALL; Cross-Sectional Shape Style: RECTANGULAR; Peripheral Shape Style: ROUND. 8 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.