The Valve,check, cataloged under National Stock Number 4820-01-233-8955, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is South London Valve & Fitting Company Ltd T/a Swagelok London. 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 4820-01-233-8955 |
| Primary Part Number | SS-8C-1/3 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | South London Valve & Fitting Company Ltd T/a Swagelok London |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Connection Style | INVERTED FLARE (PIPE) ALL ENDS |
| Mounting Position | HORIZONTAL |
| Connection Type | THREADED EXTERNAL PIPE ALL ENDS |
| Style Designator | STRAIGHT THRU |
| Operating Pressure | 3000.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.500 INCHES ALL ENDS IN |
| Seat Angle | 45.0 DEGREES ALL ENDS |
| Maximum Operating Temp | 300.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Disk Loading Method | SPRING |
| Material | STEEL COMP 316 BODY |
| Material | RUBBER PACKING |
| Material | STEEL COMP 316 FLOW CONTROL DEVICE |
| 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 |
|---|---|
| SS-8C-1/3 | South London Valve & Fitting Company Ltd T/a Swagelok London (GBR) |
| CV0238-003 | Northrop Grumman Corp Electronic Systems Defensive System Div (USA) |
| Reference | Meaning |
|---|---|
| SS-8C-1/3 | 3/9 Design control — primary reference Nupro Co |
NSN 4820-01-233-8955 is a Valve,check, manufactured by South London Valve & Fitting Company Ltd T/a Swagelok London, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-233-8955 has 2 manufacturer part numbers on file: SS-8C-1/3 (South London Valve & Fitting Company Ltd T/a Swagelok London), CV0238-003 (Northrop Grumman Corp Electronic Systems Defensive System Div).
1 possible match (shared part number, not a government interchangeability claim): 4820-01-375-5409. Verify interchangeability with system specifications before substitution.
Key specifications for SS-8C-1/3: Flow Control Device: DISK; Connection Style: INVERTED FLARE (PIPE) ALL ENDS; Mounting Position: HORIZONTAL; Connection Type: THREADED EXTERNAL 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.