The Washer,flat, cataloged under National Stock Number 5310-01-643-0688, 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 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 5310-01-643-0688 |
| Primary Part Number | 91090A113 |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Mcmaster-Carr Supply Co |
| Status | ACTIVE |
| Overall Diameter | 1.500 INCHES NOMINAL IN |
| Cross-Sectional Shape Style | BLANK RECTANGULAR |
| Surface Treatment | ZINC OVERALL |
| Peripheral Shape Style | ROUND |
| Material | STEEL OVERALL |
| Center Hole Shape Style | ROUND |
| Hole Diameter | 0.281 INCHES NOMINAL IN |
| Thickness | 0.042 INCHES MINIMUM AND 0.051 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 |
|---|---|
| 91090A113 PRIMARY | Mcmaster-Carr Supply Co (USA) |
| Reference | Meaning |
|---|---|
| 91090A113 | 3/9 Design control — primary reference Mcmaster-Carr Supply Co |
NSN 5310-01-643-0688 is a Washer,flat, manufactured by Mcmaster-Carr Supply Co, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-643-0688 has 1 manufacturer part number on file: 91090A113 (Mcmaster-Carr Supply Co).
Key specifications for 91090A113: Overall Diameter: 1.500 INCHES NOMINAL IN; Cross-Sectional Shape Style: BLANK RECTANGULAR; Special Features: PER MCMASTER CARR PART NUMBER HAS MULTIPLE SOURCES AN OEM COULD NOT BE PROVIDED; Surface Treatment: ZINC OVERALL. 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.