The Valve,check, cataloged under National Stock Number 4820-00-923-0625, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Tactair Fluid Controls Inc. Government technical data includes 26 specifications, cited from the U.S. Government catalog. The record lists 3 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 5 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government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 | 4820-00-923-0625 |
| Primary Part Number | 3318-6 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Tactair Fluid Controls Inc |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Surface Treatment Document and Classification | MIL-A-8625,TY 2 MIL SPEC SINGLE TREATMENT RESPONSE |
| Connection Style | EXTERNAL SEAT FOR GASKET SEAL (BOSS) SECOND END |
| Connection Style | FLARED (TUBE) FIRST END |
| Connection Type | THREADED EXTERNAL TUBE FIRST END |
| Connection Type | THREADED EXTERNAL BOSS SECOND END |
| Style Designator | STRAIGHT THRU |
| Nominal Outside Diameter Tube Accommodated | 0.375 INCHES SECOND END IN |
| Nominal Outside Diameter Tube Accommodated | 0.375 INCHES FIRST END IN |
| Operating Pressure | 1500.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Thread Direction | RIGHT-HAND SECOND END |
| Thread Direction | RIGHT-HAND FIRST END |
| Nominal Thread Size | 0.5625 INCHES SECOND END IN |
| Nominal Thread Size | 0.562 INCHES FIRST END IN |
| Seat Angle | 37.0 DEGREES FIRST END |
| Seat Angle | 12.0 DEGREES SECOND END |
| Disk Loading Method | SPRING |
| Surface Treatment | ANODIZE |
| Media for Which Designed | FUEL/OIL, HYDROCARBON SINGLE RESPONSE |
| Thread Class | 3A FIRST END A |
| Thread Class | 3A SECOND END A |
| Thread Quantity Per Inch | 18 FIRST END |
| Thread Quantity Per Inch | 18 SECOND END |
| Thread Series Designator | UNF FIRST END |
| Thread Series Designator | UNF SECOND 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 |
| Part Number | Manufacturer |
|---|---|
| 3318-6 PRIMARY | Tactair Fluid Controls Inc (USA) |
| 303300 PRIMARY | Eaton Aerospace Llc (USA) |
| 4CM9008D61 PRIMARY | Saf Industries Llc Dba Saf Industries Llc Div Garkenyon (USA) |
| Reference | Meaning |
|---|---|
| 303300 | 5/9 Secondary reference Eaton Corporation Dba Eaton Inoac Div Eaton |
| 3318-6 | 5/9 Secondary reference U.S. Government activity |
| 204-076-437-3 | 1/2 Source control — Government-approved source U.S. Government activity |
| 3318-6 | 5/9 Secondary reference U.S. Government activity |
| 204-076-437-003 | 5/2 Secondary reference U.S. Government activity |
NSN 4820-00-923-0625 is a Valve,check, manufactured by Tactair Fluid Controls Inc, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-00-923-0625 has 3 manufacturer part numbers on file: 3318-6 (Tactair Fluid Controls Inc), 303300 (Eaton Aerospace Llc), 4CM9008D61 (Saf Industries Llc Dba Saf Industries Llc Div Garkenyon).
2 possible matches (shared part number, not a government interchangeability claim): 5133-00-988-5688, 1005-01-604-1503. Verify interchangeability with system specifications before substitution.
Key specifications for 3318-6: Flow Control Device: POPPET; Surface Treatment Document and Classification: MIL-A-8625,TY 2 MIL SPEC SINGLE TREATMENT RESPONSE; Connection Style: EXTERNAL SEAT FOR GASKET SEAL (BOSS) SECOND END; Connection Style: FLARED (TUBE) FIRST END. 26 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.