The Valve,calibrated Flow, cataloged under National Stock Number 4820-01-409-2555, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 11 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 3 items share a part number with this NSN in the catalog (possible match — not a government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 | 4820-01-409-2555 |
| Item Name | Valve,calibrated Flow |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Second End Relationship with First End | NOT IDENTICAL |
| Body Style | STRAIGHT THRU |
| First End Style Designator | SOCKET |
| Temp Rating | 40.0 FAHRENHEIT MINIMUM AND 122.0 FAHRENHEIT MAXIMUM DEGF |
| End Connection Quantity | 2 |
| First End Connection Type | UNTHREADED INTERNAL PIPE |
| First End Nominal Pipe Size Accommodated | 0.500 INCHES IN |
| Material | ALUMINUM BODY |
| Media for Which Designed | AIR |
| Valve Discharge Flow Rate | 2992.0 GALLONS PER MINUTE AND 4488.0 GALLONS PER MINUTE |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| 281744-0004 | 3/2 Design control — primary reference U.S. Government activity |
NSN 4820-01-409-2555 is a Valve,calibrated Flow, classified under FSC 4820, Valves, Nonpowered. Status: active.
3 possible matches (shared part number, not a government interchangeability claim): 4820-01-411-8997, 4730-01-412-5219, 4820-01-412-5223. Verify interchangeability with system specifications before substitution.
Key specifications for 4820-01-409-2555: Flow Control Device: POPPET; Second End Relationship with First End: NOT IDENTICAL; Body Style: STRAIGHT THRU; First End Style Designator: SOCKET. 11 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.