The Seat,helical Compression Spring, cataloged under National Stock Number 5340-00-853-6544, is classified within Federal Supply Class 5340 (Hardware, Commercial) of the Hardware and Abrasives group. The manufacturer of record is Caterpillar Inc Div Caterpillar Defense. Government technical data includes 12 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 5340-00-853-6544 |
| Primary Part Number | 2M1778 |
| Item Name | Seat,helical Compression Spring |
| FSC / FSG | 5340 / 53 — Hardware, Commercial |
| Manufacturer | Caterpillar Inc Div Caterpillar Defense |
| Status | ACTIVE |
| Countersink Angle in Deg | 45.0 |
| First Step Diameter | 1.2500 INCHES NOMINAL IN |
| End Diameter | 0.8650 INCHES MINIMUM AND 0.8750 INCHES MAXIMUM IN |
| Countersink Diameter | 0.5410 INCHES NOMINAL IN |
| Distance From End to First Step | 0.4000 INCHES NOMINAL IN |
| Design Type | SOLID |
| Second Step Length | 0.5400 INCHES MINIMUM AND 0.5420 INCHES MAXIMUM IN |
| Style Designator | SEAT |
| Material Document and Classification | QQ-S-637,COMP B1113 FED SPEC SINGLE MATERIAL RESPONSE |
| Chamfer Angle in Deg | 45.0 |
| Bore Diameter | 0.4920 INCHES NOMINAL IN |
| Material | STEEL COMP 1213 |
| 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 |
|---|---|
| 2M1778 PRIMARY | Caterpillar Inc Div Caterpillar Defense (USA) |
| Reference | Meaning |
|---|---|
| IPD2M1778 | 5/9 Secondary reference Industrial Parts Depot, Llc Dba Ipd |
| 2M1778 | 5/9 Secondary reference Holt Bros |
NSN 5340-00-853-6544 is a Seat,helical Compression Spring, manufactured by Caterpillar Inc Div Caterpillar Defense, classified under FSC 5340, Hardware, Commercial. Status: active.
NSN 5340-00-853-6544 has 1 manufacturer part number on file: 2M1778 (Caterpillar Inc Div Caterpillar Defense).
Key specifications for 2M1778: Overall Height: 0.5000 INCHES NOMINAL IN; Countersink Angle in Deg: 45.0; First Step Diameter: 1.2500 INCHES NOMINAL IN; End Diameter: 0.8650 INCHES MINIMUM AND 0.8750 INCHES MAXIMUM IN. 12 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.