The Valve,regulating,fluid Pressure, cataloged under National Stock Number 4820-01-574-1831, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Watts Regulator Company. Government technical data includes 16 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog.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 | 4820-01-574-1831 |
| Primary Part Number | LFN55BDU 1/2" |
| Item Name | Valve,regulating,fluid Pressure |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Watts Regulator Company |
| Status | ACTIVE |
| Flow Control Device | DIAPHRAGM |
| First End Thread Direction | RIGHT-HAND |
| Second End Relationship with First End | IDENTICAL |
| Body Style | STRAIGHT THRU |
| Face to Face Distance | 4.687 INCHES NOMINAL IN |
| First End Style Designator | PLAIN |
| Temp Rating | 33.0 FAHRENHEIT MINIMUM AND 180.0 FAHRENHEIT MAXIMUM DEGF |
| End Connection Quantity | 2 |
| Outlet Pressure Range | 25.0 TO 75.0 CAMERA MOUNT |
| Valve Size | 0.500 INCHES IN |
| Valve Loading Method | SPRING |
| First End Connection Type | THREADED INTERNAL PIPE |
| Material | COPPER ALLOY BODY |
| Media for Which Designed | WATER |
| Maximum Inlet Pressure Rating | ERR-060 |
| Thread Size and Series/type Designator | 0 NPT FIRST END |
| 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 |
|---|---|
| LFN55BDU 1/2" PRIMARY | Watts Regulator Company (USA) |
| 0009536 | Watts Regulator Company (USA) |
| Reference | Meaning |
|---|---|
| N55BDU-M1 .50IN | 5/9 Secondary reference Watts Regulator Company |
| 0009937 1/2" LF X65BDU | 5/9 Secondary reference Watts Regulator Company |
NSN 4820-01-574-1831 is a Valve,regulating,fluid Pressure, manufactured by Watts Regulator Company, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-574-1831 has 2 manufacturer part numbers on file: LFN55BDU 1/2" (Watts Regulator Company), 0009536 (Watts Regulator Company).
Key specifications for LFN55BDU 1/2": Flow Control Device: DIAPHRAGM; First End Thread Direction: RIGHT-HAND; Second End Relationship with First End: IDENTICAL; Body Style: STRAIGHT THRU. 16 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.