The Seat,helical Compression Spring, cataloged under National Stock Number 5340-01-377-9140, is classified within Federal Supply Class 5340 (Hardware, Commercial) of the Hardware and Abrasives group. The manufacturer of record is Naval Sea Systems Command. Government technical data includes 10 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. Current acquisition status: Active. Unit of issue: EA.
| Parameter | Value |
|---|---|
| NSN | 5340-01-377-9140 |
| Primary Part Number | 561-6404326-6 |
| Item Name | Seat,helical Compression Spring |
| FSC / FSG | 5340 / 53 — Hardware, Commercial |
| Manufacturer | Naval Sea Systems Command |
| Status | ACTIVE |
| First Step Diameter | 1.3750 INCHES NOMINAL IN |
| End Diameter | 1.1320 INCHES MINIMUM AND 1.1370 INCHES MAXIMUM IN |
| Distance From End to First Step | 1.0200 INCHES NOMINAL IN |
| Design Type | SPLIT |
| Style Designator | SEAT |
| Material Document and Classification | QQ-B-637, 1/2H FED SPEC SINGLE MATERIAL RESPONSE |
| Second Step Diameter | 2.2500 INCHES NOMINAL IN |
| First Step Length | 1.1600 INCHES NOMINAL IN |
| Bore Diameter | 0.7500 INCHES MINIMUM AND 0.7520 INCHES MAXIMUM IN |
| Material | COPPER ALLOY 462 OR COPPER ALLOY 464 OR COPPER ALLOY 482 OR COPPER ALLOY 485 |
| 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 |
|---|---|
| 561-6404326-6 PRIMARY | Naval Sea Systems Command (USA) |
NSN 5340-01-377-9140 is a Seat,helical Compression Spring, manufactured by Naval Sea Systems Command, classified under FSC 5340, Hardware, Commercial. Status: active.
NSN 5340-01-377-9140 has 1 manufacturer part number on file: 561-6404326-6 (Naval Sea Systems Command).
Key specifications for 561-6404326-6: First Step Diameter: 1.3750 INCHES NOMINAL IN; End Diameter: 1.1320 INCHES MINIMUM AND 1.1370 INCHES MAXIMUM IN; Distance From End to First Step: 1.0200 INCHES NOMINAL IN; Design Type: SPLIT. 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.