The Piston,valve, cataloged under National Stock Number 4820-01-157-3540, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Siemens Energy, Inc.. 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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.
| Item Name | Piston,valve |
| FSC / FSG | 4820 — Valves, Nonpowered (FSG 48) |
| Manufacturers | Siemens Energy, Inc. (CAGE 16712) |
| Parameter | Value |
|---|---|
| NSN | 4820-01-157-3540 |
| Primary Part Number | M1802HD |
| Item Name | Piston,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Siemens Energy, Inc. |
| Status | ACTIVE |
| 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 |
|---|---|
| M1802HD PRIMARY | Siemens Energy, Inc. (USA) |
| Reference | Meaning |
|---|---|
| H-2257 | D/9 Drawing number reference only Siemens Energy, Inc. |
NSN 4820-01-157-3540 is a Piston,valve, manufactured by Siemens Energy, Inc., classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-157-3540 has 1 manufacturer part number on file: M1802HD (Siemens Energy, Inc.).
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.