The Valve,check, cataloged under National Stock Number 4820-01-444-4267, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Zidell Valve Corp. Government technical data includes 16 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-444-4267 |
| Primary Part Number | 0640-1/2IN |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Zidell Valve Corp |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Connection Style | PLAIN, OPTIONAL END (PIPE) ALL ENDS |
| Mounting Position | HORIZONTAL |
| Connection Type | THREADED INTERNAL PIPE ALL ENDS |
| Style Designator | STRAIGHT THRU |
| Operating Pressure | 150.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.500 INCHES ALL ENDS IN |
| Disk Loading Method | WEIGHT |
| Material | COPPER ALLOY BODY |
| Material | COPPER ALLOY FLOW CONTROL DEVICE |
| Material | COPPER ALLOY OVERALL |
| Material | COPPER ALLOY BODY LINING |
| Material | COPPER ALLOY SEAT |
| Thread Series Designator | NPT ALL ENDS |
| Valve Operation Method | AUTOMATIC |
| 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 |
|---|---|
| 0640-1/2IN PRIMARY | Zidell Valve Corp (USA) |
| Reference | Meaning |
|---|---|
| 0640-1/2IN | 5/9 Secondary reference Fairbanks Co the |
NSN 4820-01-444-4267 is a Valve,check, manufactured by Zidell Valve Corp, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-444-4267 has 1 manufacturer part number on file: 0640-1/2IN (Zidell Valve Corp).
Key specifications for 0640-1/2IN: Flow Control Device: DISK; Connection Style: PLAIN, OPTIONAL END (PIPE) ALL ENDS; Mounting Position: HORIZONTAL; Connection Type: THREADED INTERNAL PIPE ALL ENDS. 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.