The Seat,helical Compression Spring, cataloged under National Stock Number 5340-00-905-2759, is classified within Federal Supply Class 5340 (Hardware, Commercial) of the Hardware and Abrasives group. The manufacturer of record is Hamilton Sundstrand Corporation Dba Collins Aerospace. Government technical data includes 9 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 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active. Unit of issue: EA.
| Parameter | Value |
|---|---|
| NSN | 5340-00-905-2759 |
| Primary Part Number | 556593 |
| Item Name | Seat,helical Compression Spring |
| FSC / FSG | 5340 / 53 — Hardware, Commercial |
| Manufacturer | Hamilton Sundstrand Corporation Dba Collins Aerospace |
| Status | ACTIVE |
| FSC Application Data | ACFT CABIN PRESSURIZATION SYSTEM |
| First Step Diameter | 1.1200 INCHES NOMINAL IN |
| End Diameter | 0.8710 INCHES MINIMUM AND 0.8790 INCHES MAXIMUM IN |
| Distance From End to First Step | 0.2100 INCHES NOMINAL IN |
| Design Type | SOLID |
| Style Designator | SEAT |
| Surface Treatment | ANODIZE |
| Bore Diameter | 0.7550 INCHES MINIMUM AND 0.7650 INCHES MAXIMUM IN |
| Material | ALUMINUM ALLOY |
| 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 |
|---|---|
| 556593 PRIMARY | Hamilton Sundstrand Corporation Dba Collins Aerospace (USA) |
NSN 5340-00-905-2759 is a Seat,helical Compression Spring, manufactured by Hamilton Sundstrand Corporation Dba Collins Aerospace, classified under FSC 5340, Hardware, Commercial. Status: active.
NSN 5340-00-905-2759 has 1 manufacturer part number on file: 556593 (Hamilton Sundstrand Corporation Dba Collins Aerospace).
1 possible match (shared part number, not a government interchangeability claim): 6685-01-489-7032. Verify interchangeability with system specifications before substitution.
Key specifications for 556593: Overall Height: 0.2600 INCHES NOMINAL IN; FSC Application Data: ACFT CABIN PRESSURIZATION SYSTEM; First Step Diameter: 1.1200 INCHES NOMINAL IN; End Diameter: 0.8710 INCHES MINIMUM AND 0.8790 INCHES MAXIMUM IN. 9 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.