The Valve,check, cataloged under National Stock Number 4820-01-421-4704, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 16 specifications, cited from the U.S. Government catalog. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 6 items share a part number with this NSN in the catalog (possible match — not a government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 | 4820-01-421-4704 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Flange Shape | ROUND WITH HOLES ALL ENDS |
| Flange Face Design | PLAIN ALL ENDS |
| Bolt Circle Nominal Diameter | 7.500 INCHES ALL ENDS IN |
| Mounting Position | VERTICAL |
| Connection Type | FLANGE ALL ENDS |
| Style Designator | STRAIGHT THRU FLANGED ENDS |
| Bolt Hole Nominal Diameter | 0.750 INCHES ALL ENDS IN |
| Operating Pressure | 285.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Valve Size | 4.000 INCHES IN |
| Nominal Outside Diameter | 9.000 INCHES ALL ENDS IN |
| Disk Loading Method | SPRING |
| Bolt Hole Quantity | 8 ALL ENDS |
| Face to Face Distance | 6.880 INCHES IN |
| Material | COPPER ALLOY 922 BODY |
| Valve Operation Method | AUTOMATIC |
| Nominal Thickness | 0.687 INCHES ALL ENDS IN |
| 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 |
|---|---|
| G15BAPP-72 4.00 INCH | 5/2 Secondary reference U.S. Government activity |
| CD0028 4.00 IN | 3/2 Design control — primary reference U.S. Government activity |
| G15XPP-72 4.00IN | 5/9 Secondary reference U.S. Government activity |
| CD0028 | D/9 Drawing number reference only U.S. Government activity |
NSN 4820-01-421-4704 is a Valve,check, classified under FSC 4820, Valves, Nonpowered. Status: active.
6 possible matches (shared part number, not a government interchangeability claim): 4820-01-421-4706, 4820-01-421-4712, 4820-01-508-5419. Verify interchangeability with system specifications before substitution.
Key specifications for 4820-01-421-4704: Flange Shape: ROUND WITH HOLES ALL ENDS; Flange Face Design: PLAIN ALL ENDS; Bolt Circle Nominal Diameter: 7.500 INCHES ALL ENDS IN; Mounting Position: VERTICAL. 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.