The Washer,flat, cataloged under National Stock Number 5310-01-234-0380, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Steward Machine Co Inc. 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 5310-01-234-0380 |
| Primary Part Number | 642-495 |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Steward Machine Co Inc |
| Status | ACTIVE |
| Surface Finish | 63.0 MICROINCHES ALL SURFACES |
| Overall Diameter | 0.594 INCHES NOMINAL IN |
| Material Document and Classification | ASTM A108 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Cross-Sectional Shape Style | RECTANGULAR |
| Peripheral Shape Style | ROUND |
| Material | STEEL COMP 1020 OVERALL |
| Center Hole Shape Style | ROUND |
| Hole Diameter | 0.391 INCHES NOMINAL IN |
| Thickness | 0.094 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 |
|---|---|
| 642-495 PRIMARY | Steward Machine Co Inc (USA) |
| Reference | Meaning |
|---|---|
| 60-642 PIECE 495 | 5/9 Secondary reference Hardie-Tynes Co., Inc. |
| 642-495 | 3/9 Design control — primary reference Hardie-Tynes Co., Inc. |
NSN 5310-01-234-0380 is a Washer,flat, manufactured by Steward Machine Co Inc, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-234-0380 has 1 manufacturer part number on file: 642-495 (Steward Machine Co Inc).
1 possible match (shared part number, not a government interchangeability claim): 5930-01-573-0795. Verify interchangeability with system specifications before substitution.
Key specifications for 642-495: Surface Finish: 63.0 MICROINCHES ALL SURFACES; Overall Diameter: 0.594 INCHES NOMINAL IN; Material Document and Classification: ASTM A108 ASSN STD 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.