The Valve,check, cataloged under National Stock Number 4820-00-266-9503, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 14 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 3 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-266-9503 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Nominal Pipe Size Accommodated | 0.840 INCHES ALL ENDS IN |
| Connection Style | SOCKET (PIPE) ALL ENDS |
| Mounting Position | HORIZONTAL OR VERTICAL |
| Connection Type | UNTHREADED INTERNAL TUBE ALL ENDS |
| Style Designator | STRAIGHT THRU |
| Operating Pressure | 200.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Maximum Operating Temp | 425.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Media for Which Designed | STEAM SINGLE RESPONSE |
| Material | COPPER ALLOY BODY |
| Material | COPPER ALLOY FLOW CONTROL DEVICE |
| Material | COPPER ALLOY SEAT |
| Valve Operation Method | AUTOMATIC |
| Reference Number Differentiating Characteristics | AS DIFFERENTIATEDBY VALVE SIZE |
| 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 |
|---|---|
| B194 | 3/1 Design control — primary reference U.S. Government activity |
NSN 4820-00-266-9503 is a Valve,check, classified under FSC 4820, Valves, Nonpowered. Status: active.
3 possible matches (shared part number, not a government interchangeability claim): 4820-00-266-9506, 5330-00-352-3053, 3110-00-516-5289. Verify interchangeability with system specifications before substitution.
Key specifications for 4820-00-266-9503: Flow Control Device: DISK; Nominal Pipe Size Accommodated: 0.840 INCHES ALL ENDS IN; Connection Style: SOCKET (PIPE) ALL ENDS; Mounting Position: HORIZONTAL OR VERTICAL. 14 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.