The Washer,flat, cataloged under National Stock Number 5310-01-494-2391, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Naval Sea Systems Command. Government technical data includes 9 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 5 items share a part number with this NSN in the catalog (possible match — not a government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 | 5310-01-494-2391 |
| Primary Part Number | 122-4734979 P/N 19 |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Naval Sea Systems Command |
| Status | ACTIVE |
| Overall Diameter | 1.688 INCHES NOMINAL IN |
| Hardness Rating | 36.0 ROCKWELL C MINIMUM AND 40.0 ROCKWELL C MAXIMUM |
| Material Document and Classification | MIL-S-5000E MIL SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Cross-Sectional Shape Style | RECTANGULAR |
| Peripheral Shape Style | ROUND |
| Material | STEEL COMP E4340 OVERALL |
| Center Hole Shape Style | ROUND |
| Hole Diameter | 0.812 INCHES NOMINAL IN |
| Thickness | 0.062 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 |
|---|---|
| 122-4734979 P/N 19 PRIMARY | Naval Sea Systems Command (USA) |
| Reference | Meaning |
|---|---|
| 4734979 | D/9 Drawing number reference only Naval Sea Systems Command |
NSN 5310-01-494-2391 is a Washer,flat, manufactured by Naval Sea Systems Command, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-494-2391 has 1 manufacturer part number on file: 122-4734979 P/N 19 (Naval Sea Systems Command).
5 possible matches (shared part number, not a government interchangeability claim): 5310-01-494-2392, 5310-01-494-2393, 3040-01-496-9253. Verify interchangeability with system specifications before substitution.
Key specifications for 122-4734979 P/N 19: Overall Diameter: 1.688 INCHES NOMINAL IN; Hardness Rating: 36.0 ROCKWELL C MINIMUM AND 40.0 ROCKWELL C MAXIMUM; Material Document and Classification: MIL-S-5000E MIL SPEC SINGLE MATERIAL RESPONSE OVERALL; Cross-Sectional Shape Style: RECTANGULAR. 9 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.