The Valve,check, cataloged under National Stock Number 4820-00-988-8323, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 19 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-988-8323 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Connection Style | FLARED (TUBE) ALL ENDS |
| Mounting Position | HORIZONTAL OR VERTICAL |
| Connection Type | THREADED EXTERNAL TUBE ALL ENDS |
| Style Designator | STRAIGHT THRU |
| Nominal Outside Diameter Tube Accommodated | 0.750 INCHES ALL ENDS IN |
| Operating Pressure | 310.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 1.500 INCHES ALL ENDS IN |
| Seat Angle | 37.0 DEGREES ALL ENDS |
| Disk Loading Method | SPRING |
| Media for Which Designed | AIR SINGLE RESPONSE |
| Thread Class | 3A ALL ENDS A |
| Thread Quantity Per Inch | 12 ALL ENDS |
| Material | ALUMINUM ALLOY FLOW CONTROL DEVICE |
| Material | ALUMINUM ALLOY SEAT |
| Material | ALUMINUM ALLOY BODY |
| Thread Series Designator | UN 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 |
| Reference | Meaning |
|---|---|
| 7-761-101 | 3/2 Design control — primary reference U.S. Government activity |
NSN 4820-00-988-8323 is a Valve,check, classified under FSC 4820, Valves, Nonpowered. Status: active.
1 possible match (shared part number, not a government interchangeability claim): 5935-01-366-6031. Verify interchangeability with system specifications before substitution.
Key specifications for 4820-00-988-8323: Flow Control Device: POPPET; Connection Style: FLARED (TUBE) ALL ENDS; Mounting Position: HORIZONTAL OR VERTICAL; Connection Type: THREADED EXTERNAL TUBE ALL ENDS. 19 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.