The Seat,helical Compression Spring, cataloged under National Stock Number 5340-01-221-0278, is classified within Federal Supply Class 5340 (Hardware, Commercial) of the Hardware and Abrasives group. Government technical data includes 8 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active. Unit of issue: EA.
| Parameter | Value |
|---|---|
| NSN | 5340-01-221-0278 |
| Item Name | Seat,helical Compression Spring |
| FSC / FSG | 5340 / 53 — Hardware, Commercial |
| Status | ACTIVE |
| First Step Diameter | 0.6100 INCHES MINIMUM AND 0.6300 INCHES MAXIMUM IN |
| End Diameter | 0.4800 INCHES MINIMUM AND 0.4900 INCHES MAXIMUM IN |
| Distance From End to First Step | 0.0800 INCHES NOMINAL IN |
| Design Type | SOLID |
| Style Designator | SEAT |
| Material Document and Classification | QQ-S-763, CLASS 302, 304, 305, 309, 310, 317, OR CLASS 347 FED SPEC ALL MATERIAL RESPONSES OR QQ-S-766, CLASS 301, 302, 3O4, 305, 309, 310, 316, 321, 323, 347, 348 FED SPEC ALL MATERIAL RESPONSES OR MIL-S-5059, COMP 301, 302, 304, OR 316 MIL SPEC ALL MATERIAL RESPONSES |
| Bore Diameter | 0.2970 INCHES MINIMUM AND 0.3000 INCHES MAXIMUM IN |
| Material | STEEL COMP 301 OR STEEL COMP 302 OR STEEL COMP 304 OR STEEL COMP 305 OR STEEL COMP 309 OR STEEL COMP 310 OR STEEL COMP 316 OR STEEL COMP 317 OR STEEL COMP 321 OR STEEL COMP 323 OR STEEL COMP 347 OR STEEL COMP 348 |
| 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 |
| Reference | Meaning |
|---|---|
| S9404-96 | 5/9 Secondary reference Honeywell International Inc. Dba Honeywell International Div Aerospace - Tempe (west Warner Road) |
| S9404-96 | 3/2 Design control — primary reference U.S. Government activity |
NSN 5340-01-221-0278 is a Seat,helical Compression Spring, classified under FSC 5340, Hardware, Commercial. Status: active.
Key specifications for 5340-01-221-0278: Overall Height: 0.1200 INCHES MINIMUM AND 0.1400 INCHES MAXIMUM IN; First Step Diameter: 0.6100 INCHES MINIMUM AND 0.6300 INCHES MAXIMUM IN; End Diameter: 0.4800 INCHES MINIMUM AND 0.4900 INCHES MAXIMUM IN; Distance From End to First Step: 0.0800 INCHES NOMINAL IN. 8 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.