The Piston,hydrostarter, cataloged under National Stock Number 2990-00-657-7580, is classified within Federal Supply Class 2990 (Miscellaneous Engine Accessories, Nonaircraft) of the Engine Accessories group. The manufacturer of record is Rolls-Royce Solutions America Inc. Government technical data includes 1 specification, 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 2990-00-657-7580 |
| Primary Part Number | 6525020 |
| Item Name | Piston,hydrostarter |
| FSC / FSG | 2990 / 29 — Miscellaneous Engine Accessories, Nonaircraft |
| Manufacturer | Rolls-Royce Solutions America Inc |
| Status | ACTIVE |
| General Characteristics Item Description | STEEL; 2.935 IN. O/A LG; 2.735 IN. LG CYLINDER,2.625 IN. LG PISTON; 0.750 IN. CYLINDER OD; 0.500 IN. PISTON ID,0.709 IN. PISTON OD IN |
| 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 |
|---|---|
| 6525020 PRIMARY | Rolls-Royce Solutions America Inc (USA) |
| Reference | Meaning |
|---|---|
| 6525020 | 5/9 Secondary reference General Motors Corp |
NSN 2990-00-657-7580 is a Piston,hydrostarter, manufactured by Rolls-Royce Solutions America Inc, classified under FSC 2990, Miscellaneous Engine Accessories, Nonaircraft. Status: active.
NSN 2990-00-657-7580 has 1 manufacturer part number on file: 6525020 (Rolls-Royce Solutions America Inc).
Key specifications for 6525020: General Characteristics Item Description: STEEL; 2.935 IN. O/A LG; 2.735 IN. LG CYLINDER,2.625 IN. LG PISTON; 0.750 IN. CYLINDER OD; 0.500 IN. PISTON ID,0.709 IN. PISTON OD IN. 1 specification is 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.