The Washer,flat, cataloged under National Stock Number 5310-01-576-2273, is classified within Federal Supply Class 5310 (Nuts and Washers) of the Hardware and Abrasives group. The manufacturer of record is Trico Manufacturing Inc.. Government technical data includes 7 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 5310-01-576-2273 |
| Primary Part Number | 4M307-5-21 |
| Item Name | Washer,flat |
| FSC / FSG | 5310 / 53 — Nuts and Washers |
| Manufacturer | Trico Manufacturing Inc. |
| Status | ACTIVE |
| Overall Diameter | 1.734 INCHES NOMINAL IN |
| Cross-Sectional Shape Style | RECTANGULAR |
| Peripheral Shape Style | ROUND |
| Material | ALUMINUM ALLOY 6061 OVERALL |
| Center Hole Shape Style | ROUND |
| Hole Diameter | 0.328 INCHES NOMINAL IN |
| Thickness | 0.025 INCHES NOMINAL IN |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL Q — CCL Item — Commerce Control List |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| 4M307-5-21 PRIMARY | Trico Manufacturing Inc. (USA) |
| 4M307-5-21 | The Boeing Company Div Defense (USA) |
| Reference | Meaning |
|---|---|
| 4M307-5-21 | 5/9 Secondary reference U.S. Government activity |
NSN 5310-01-576-2273 is a Washer,flat, manufactured by Trico Manufacturing Inc., classified under FSC 5310, Nuts and Washers. Status: active.
NSN 5310-01-576-2273 has 2 manufacturer part numbers on file: 4M307-5-21 (Trico Manufacturing Inc.), 4M307-5-21 (The Boeing Company Div Defense).
Key specifications for 4M307-5-21: Overall Diameter: 1.734 INCHES NOMINAL IN; Cross-Sectional Shape Style: RECTANGULAR; Peripheral Shape Style: ROUND; End Item Identification: F-15 AIRCRAFT. 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.
NSN 5310-01-576-2273 has DEMIL Code Q. Demilitarization may be required before disposal or transfer to non-military entities.
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.