The Washer,flat, cataloged under National Stock Number 5310-01-376-3555, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Heckler & Koch Defense Inc Dba Hkd Div Heckler and Koch Defense Inc. 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Item Name | Washer,flat |
| FSC / FSG | 5310 — Nuts and Washers (FSG 53) |
| Manufacturers | Heckler & Koch Defense Inc Dba Hkd Div Heckler and Koch Defense Inc (CAGE 3HN73) |
| Parameter | Value |
|---|---|
| NSN | 5310-01-376-3555 |
| Primary Part Number | 200371 |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Heckler & Koch Defense Inc Dba Hkd Div Heckler and Koch Defense Inc |
| Status | ACTIVE |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Part Number | Manufacturer |
|---|---|
| 200371 PRIMARY | Heckler & Koch Defense Inc Dba Hkd Div Heckler and Koch Defense Inc (USA) |
| Reference | Meaning |
|---|---|
| 200371 | 3/9 Design control — primary reference Heckler & Koch, Inc. |
NSN 5310-01-376-3555 is a Washer,flat, manufactured by Heckler & Koch Defense Inc Dba Hkd Div Heckler and Koch Defense Inc, classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-376-3555 has 1 manufacturer part number on file: 200371 (Heckler & Koch Defense Inc Dba Hkd Div Heckler and Koch Defense Inc).
1 possible match (shared part number, not a government interchangeability claim): 6110-01-543-9532. Verify interchangeability with system specifications before substitution.
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.