The Valve,vent, cataloged under National Stock Number 4820-01-155-0320, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Acme Products & Engineering Inc. Government technical data includes 9 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government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 | 4820-01-155-0320 |
| Primary Part Number | 181-5023AP |
| Item Name | Valve,vent |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Acme Products & Engineering Inc |
| Status | ACTIVE |
| Furnished Items and Quantity | 1 GASKET |
| Connection Style | PLAIN (TUBE) ALL ENDS |
| Connection Type | THREADED EXTERNAL TUBE ALL ENDS |
| Style Designator | ANGLE |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.313 INCHES ALL ENDS IN |
| Thread Class | 3A ALL ENDS A |
| Material | COPPER ALLOY OVERALL |
| Thread Series Designator | UNF ALL ENDS |
| 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 |
|---|---|
| 181-5023AP PRIMARY | Acme Products & Engineering Inc (USA) |
| Reference | Meaning |
|---|---|
| 181-5300 | D/9 Drawing number reference only Fluid Power Components Inc |
| 181-5300 ITEM 23 | 5/9 Secondary reference Fluid Power Components Inc |
| 181-5023 | 5/9 Secondary reference Fluid Power Components Inc |
NSN 4820-01-155-0320 is a Valve,vent, manufactured by Acme Products & Engineering Inc, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-155-0320 has 1 manufacturer part number on file: 181-5023AP (Acme Products & Engineering Inc).
2 possible matches (shared part number, not a government interchangeability claim): 4330-01-156-6126, 4730-01-157-6381. Verify interchangeability with system specifications before substitution.
Key specifications for 181-5023AP: Furnished Items and Quantity: 1 GASKET; Connection Style: PLAIN (TUBE) ALL ENDS; Connection Type: THREADED EXTERNAL TUBE ALL ENDS; Style Designator: ANGLE. 9 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.