The Valve,expansion, cataloged under National Stock Number 4820-01-466-3898, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Atmost Refrigeration Company, Inc. Div Atmost Refrigeration. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-466-3898 |
| Primary Part Number | EFS-1/4ZP |
| Item Name | Valve,expansion |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Atmost Refrigeration Company, Inc. Div Atmost Refrigeration |
| 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 |
|---|---|
| EFS-1/4ZP PRIMARY | Atmost Refrigeration Company, Inc. Div Atmost Refrigeration (USA) |
| Reference | Meaning |
|---|---|
| AA1/4RW45 | 5/9 Secondary reference Atmost Refrigeration Company, Inc. Div Atmost Refrigeration |
| AA1/4RW35 | 5/9 Secondary reference Atmost Refrigeration Company, Inc. Div Atmost Refrigeration |
| NAV-18-LT-BMC | D/9 Drawing number reference only Atmost Refrigeration Company, Inc. Div Atmost Refrigeration |
NSN 4820-01-466-3898 is a Valve,expansion, manufactured by Atmost Refrigeration Company, Inc. Div Atmost Refrigeration, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-466-3898 has 1 manufacturer part number on file: EFS-1/4ZP (Atmost Refrigeration Company, Inc. Div Atmost Refrigeration).
1 possible match (shared part number, not a government interchangeability claim): 4110-01-466-8062. Verify interchangeability with system specifications before substitution.
Key specifications for EFS-1/4ZP: Special Features: NHA MODULE FREEZER; End Item Identification: NIMITZ CLASS CVN. 0 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.