The Air Lock Valve, cataloged under National Stock Number 4820-01-053-5159, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is General Machine Works, Inc.. Government technical data includes 2 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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.
| Parameter | Value |
|---|---|
| NSN | 4820-01-053-5159 |
| Primary Part Number | 164-A-6 |
| Item Name | Air Lock Valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | General Machine Works, Inc. |
| Status | ACTIVE |
| General Characteristics Item Description | SPRING LOADED;ZINC BASE ALLOY BODY; 3 PORTS INTERNALLY THREADED; 1/4-18 NPT; 2 MTG SLOTS 0.438 IN. WIDE BY 0.688 IN. LG IN |
| Material | ZINC ALLOY |
| 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 |
|---|---|
| 164A-1X164A-6 | General Machine Works, Inc. (USA) |
| 164-A-6 PRIMARY | General Machine Works, Inc. (USA) |
| Reference | Meaning |
|---|---|
| 164-A-6 | 3/9 Design control — primary reference General Regulator Corp. Dba Accudriv |
| 164A-1X164A-6 | 5/9 Secondary reference General Regulator Corp. Dba Accudriv |
NSN 4820-01-053-5159 is a Air Lock Valve, manufactured by General Machine Works, Inc., classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-053-5159 has 2 manufacturer part numbers on file: 164A-1X164A-6 (General Machine Works, Inc.), 164-A-6 (General Machine Works, Inc.).
Key specifications for 164-A-6: General Characteristics Item Description: SPRING LOADED;ZINC BASE ALLOY BODY; 3 PORTS INTERNALLY THREADED; 1/4-18 NPT; 2 MTG SLOTS 0.438 IN. WIDE BY 0.688 IN. LG IN; Material: ZINC ALLOY. 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.