The Rod,piston,hydraulic Accumulator, cataloged under National Stock Number 3040-01-500-7984, is classified within Federal Supply Class 3040 (Miscellaneous Power Transmission Equipment) of the Mechanical Power Transmission Equipment group. The manufacturer of record is Naval Sea Systems Command. Government technical data includes 2 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 3040-01-500-7984 |
| Primary Part Number | 556-6985454-4A |
| Item Name | Rod,piston,hydraulic Accumulator |
| FSC / FSG | 3040 / 30 — Miscellaneous Power Transmission Equipment |
| Manufacturer | Naval Sea Systems Command |
| Status | ACTIVE |
| Overall Diameter | 2.746 INCHES MINIMUM AND 2.748 INCHES MAXIMUM IN |
| Material | STEEL CORROSION RESISTING |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| 556-6985454-4A PRIMARY | Naval Sea Systems Command (USA) |
| Reference | Meaning |
|---|---|
| 556-6985454 | D/9 Drawing number reference only Naval Sea Systems Command |
| H642-6930-4A | 5/2 Secondary reference U.S. Government activity |
NSN 3040-01-500-7984 is a Rod,piston,hydraulic Accumulator, manufactured by Naval Sea Systems Command, classified under FSC 3040, Miscellaneous Power Transmission Equipment. Status: active.
NSN 3040-01-500-7984 has 1 manufacturer part number on file: 556-6985454-4A (Naval Sea Systems Command).
2 possible matches (shared part number, not a government interchangeability claim): 3040-01-500-8024, 3040-01-500-9029. Verify interchangeability with system specifications before substitution.
Key specifications for 556-6985454-4A: Overall Diameter: 2.746 INCHES MINIMUM AND 2.748 INCHES MAXIMUM IN; Overall Length: 43.560 INCHES NOMINAL IN; Special Features: PISTON ROD IS HOLLOW WITH A 1.25 INCH INSIDE DIAMETER.BOTH ENDS HAVE A CROSS SECTION THRU HOLE. SHOULDERED ROD ATTACHES TO THE ACCUMULATOR PISTON. IN; Part Name Assigned by Controlling Agency: TAILROD,PISTON. 2 specifications are documented in the U.S. Government catalog.
No hazard code in the DLA record (HMIC N). 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.