The Valve,check, cataloged under National Stock Number 4820-00-138-3898, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 20 specifications, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-138-3898 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Connection Style | FLARED (TUBE) ALL ENDS |
| Style Designator | STRAIGHT THRU |
| Material Document and Classification | FED-STD-66, AISI 304/SAE 30304 FED STD SINGLE MATERIAL RESPONSE FLOW CONTROL DEVICE |
| Material Document and Classification | QQ-A-250/4,ALLOY 2024 FED SPEC SINGLE MATERIAL RESPONSE BODY |
| Material Document and Classification | QQ-A-250/4,ALLOY 2024 FED SPEC SINGLE MATERIAL RESPONSE SEAT |
| Operating Pressure | 600.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.375 INCHES ALL ENDS IN |
| Seat Angle | 37.0 DEGREES ALL ENDS |
| Maximum Operating Temp | 180.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Disk Loading Method | SPRING |
| Media for Which Designed | NITROGEN, GASEOUS SECOND RESPONSE |
| Media for Which Designed | AIR FIRST RESPONSE |
| Thread Class | 3A ALL ENDS A |
| Material | ALUMINUM ALLOY 2024 BODY |
| Material | ALUMINUM ALLOY 2024 SEAT |
| Material | RUBBER SYNTHETIC AND STEEL COMP 304 FLOW CONTROL DEVICE |
| Thread Series Designator | UNF 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 |
|---|---|
| 869A3T4T7 | 3/2 Design control — primary reference U.S. Government activity |
| C6217A3M4M7 | 7/2 Vendor item drawing reference U.S. Government activity |
NSN 4820-00-138-3898 is a Valve,check, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-00-138-3898: Flow Control Device: POPPET; Connection Style: FLARED (TUBE) ALL ENDS; Style Designator: STRAIGHT THRU; Material Document and Classification: FED-STD-66, AISI 304/SAE 30304 FED STD SINGLE MATERIAL RESPONSE FLOW CONTROL DEVICE. 20 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.