The Washer,flat, cataloged under National Stock Number 5310-01-371-2391, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Bsi Standards Limited. Government technical data includes 7 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 5310-01-371-2391 |
| Primary Part Number | BS4320-M2.5TYPEA |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Bsi Standards Limited |
| Status | ACTIVE |
| Overall Diameter | 6.2 MILLIMETERS MINIMUM AND 6.5 MILLIMETERS MAXIMUM MM |
| Cross-Sectional Shape Style | RECTANGULAR |
| Peripheral Shape Style | ROUND |
| Material | STEEL OVERALL |
| Center Hole Shape Style | ROUND |
| Hole Diameter | 2.7 MILLIMETERS MINIMUM AND 2.8 MILLIMETERS MAXIMUM MM |
| Thickness | 0.4 MILLIMETERS MINIMUM AND 0.6 MILLIMETERS MAXIMUM MM |
| 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 |
|---|---|
| BS4320-M2.5TYPEA | Bsi Standards Limited (GBR) |
| Reference | Meaning |
|---|---|
| DIN125A 2.5MM | 3/9 Design control — primary reference Metric and Multistandard Components Corp |
NSN 5310-01-371-2391 is a Washer,flat, manufactured by Bsi Standards Limited, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-371-2391 has 1 manufacturer part number on file: BS4320-M2.5TYPEA (Bsi Standards Limited).
Key specifications for BS4320-M2.5TYPEA: Overall Diameter: 6.2 MILLIMETERS MINIMUM AND 6.5 MILLIMETERS MAXIMUM MM; Cross-Sectional Shape Style: RECTANGULAR; Peripheral Shape Style: ROUND; Material: STEEL OVERALL. 7 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.