The Valve,check, cataloged under National Stock Number 4820-01-195-8422, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Union Carbide Corp Sub of Dow Co the. 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. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-195-8422 |
| Primary Part Number | 639110 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Union Carbide Corp Sub of Dow Co the |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Connection Style | PLAIN (HOSE) FIRST END |
| Connection Style | FLARE (TUBE) SECOND END |
| Mounting Position | HORIZONTAL OR VERTICAL |
| Connection Type | THREADED EXTERNAL HOSE FIRST END |
| Connection Type | THREADED INTERNAL TUBE SECOND END |
| Style Designator | STRAIGHT THRU |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.562 INCHES ALL ENDS IN |
| Media for Which Designed | OXYGEN, GASEOUS SINGLE RESPONSE |
| Thread Class | 3B SECOND END |
| Thread Quantity Per Inch | 11-1/2 FIRST END |
| Material | COPPER ALLOY BODY |
| Thread Series Designator | UNF SECOND END |
| Thread Series Designator | NH FIRST END |
| 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 |
NSN 4820-01-195-8422 is a Valve,check, manufactured by Union Carbide Corp Sub of Dow Co the, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-195-8422 has 2 manufacturer part numbers on file: 7957A1 (Mcmaster-Carr Supply Co), 639110 (Union Carbide Corp Sub of Dow Co the).
Key specifications for 639110: Flow Control Device: DISK; Connection Style: PLAIN (HOSE) FIRST END; Connection Style: FLARE (TUBE) SECOND END; Mounting Position: HORIZONTAL OR VERTICAL. 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.