The Seat,helical Compression Spring, cataloged under National Stock Number 5340-01-284-5321, is classified within Federal Supply Class 5340 (Hardware, Commercial) of the Hardware and Abrasives group. The manufacturer of record is Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier. Government technical data includes 10 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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. Unit of issue: EA.
| Parameter | Value |
|---|---|
| NSN | 5340-01-284-5321 |
| Primary Part Number | 2129564 |
| Item Name | Seat,helical Compression Spring |
| FSC / FSG | 5340 / 53 — Hardware, Commercial |
| Manufacturer | Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier |
| Status | ACTIVE |
| First Step Diameter | 4.6250 INCHES NOMINAL IN |
| End Diameter | 3.1870 INCHES NOMINAL IN |
| Surface Treatment Document and Classification | MIL-A-8625, TYPE 2, CLASS 1 MIL SPEC SINGLE TREATMENT RESPONSE |
| Second End Diameter | 4.3990 INCHES MINIMUM AND 4.4400 INCHES MAXIMUM IN |
| Distance From End to First Step | 0.9680 INCHES NOMINAL IN |
| Design Type | SOLID |
| Counterbore Diameter | 2.3120 INCHES MINIMUM AND 2.3130 INCHES MAXIMUM IN |
| Surface Treatment | ANODIZE |
| Bore Diameter | 1.9370 INCHES NOMINAL IN |
| Material | ALUMINUM ALLOY 6061 |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | Possible hazard — SDS may be required (DLA HMIC P) |
| Criticality Code | X |
| Unit of Issue | EA |
| Part Number | Manufacturer |
|---|---|
| 2129564 | Bae Systems Land & Armaments L.p. (USA) |
| 2129564 PRIMARY | Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier (USA) |
| Reference | Meaning |
|---|---|
| 5340PL0897880 | 6/9 Informative reference only Jednolity Indeks Materialowy - Uniform Material Index |
NSN 5340-01-284-5321 is a Seat,helical Compression Spring, manufactured by Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier, classified under FSC 5340, Hardware, Commercial. Status: active.
NSN 5340-01-284-5321 has 2 manufacturer part numbers on file: 2129564 (Bae Systems Land & Armaments L.p.), 2129564 (Navair and Navsea Managed Original Design Activity Dwg Not Material/parts Supplier).
Key specifications for 2129564: Overall Height: 2.1560 INCHES NOMINAL IN; First Step Diameter: 4.6250 INCHES NOMINAL IN; End Diameter: 3.1870 INCHES NOMINAL IN; Surface Treatment Document and Classification: MIL-A-8625, TYPE 2, CLASS 1 MIL SPEC SINGLE TREATMENT RESPONSE. 10 specifications are documented in the U.S. Government catalog.
Possible hazard — SDS may be required (DLA HMIC P). 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.