The Diaphragm,valve,flat, cataloged under National Stock Number 4820-00-326-6003, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Hunt Valve Company, Inc.. Government technical data includes 5 specifications, cited from the U.S. Government catalog. The record lists 24 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 26 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-326-6003 |
| Primary Part Number | AA19821-8PC19821-55 |
| Item Name | Diaphragm,valve,flat |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Hunt Valve Company, Inc. |
| Status | ACTIVE |
| Outside Diameter | 3.750 INCHES NOMINAL IN |
| Style Designator | FLAT |
| Material Thickness | 0.024 INCHES NOMINAL IN |
| Center Hole Diameter | 0.772 INCHES NOMINAL IN |
| Material | STEEL CORROSION RESISTING |
| 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 |
|---|---|
| AA19821-8PC19821-55 PRIMARY | Hunt Valve Company, Inc. (USA) |
| AA19821-3PC19821-54 PRIMARY | Hunt Valve Company, Inc. (USA) |
| AA23178PC23178-54 PRIMARY | Hunt Valve Company, Inc. (USA) |
| AA20045PC20044-55 PRIMARY | Hunt Valve Company, Inc. (USA) |
| AA23148PC23148-55 PRIMARY | Hunt Valve Company, Inc. (USA) |
| AA23742PC23742-55 PRIMARY | Hunt Valve Company, Inc. (USA) |
| AA19819-1PC54 PRIMARY | Hunt Valve Company, Inc. (USA) |
| AA23017PC23017-54 PRIMARY | Hunt Valve Company, Inc. (USA) |
| AA22055PC22052-54 PRIMARY | Hunt Valve Company, Inc. (USA) |
| AA22052-1PC22052-54 PRIMARY | Hunt Valve Company, Inc. (USA) |
| AA23017PC23017-55 PRIMARY | Hunt Valve Company, Inc. (USA) |
| AA19821PC19821-4 PRIMARY | Hunt Valve Company, Inc. (USA) |
| AA21041PC19821-54 PRIMARY | Hunt Valve Company, Inc. (USA) |
| AA23178PC178-55 PRIMARY | Hunt Valve Company, Inc. (USA) |
| AA9821-3PC19821-55 PRIMARY | Hunt Valve Company, Inc. (USA) |
| AA20045PC20044-54 PRIMARY | Hunt Valve Company, Inc. (USA) |
| AA19819-1PC55 PRIMARY | Hunt Valve Company, Inc. (USA) |
| AA22052PC22052-54 PRIMARY | Hunt Valve Company, Inc. (USA) |
| AA19821-2PC19821-54 PRIMARY | Hunt Valve Company, Inc. (USA) |
| AA21041-2PC19821-55 PRIMARY | Hunt Valve Company, Inc. (USA) |
| Reference | Meaning |
|---|---|
| AA21041PC19821-54 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| D18271QC | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| AA22055PC22052-55 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| AA19821PC19821-4 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| AA21041-1PC19821-54 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| AA23019PC23017-55 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| AA20044PC20044-54 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| AA23148PC23148-55 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| AA23178PC178-55 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| AA23742PC23742-54 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| AA22055PC22052-54 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| AA23178PC23178-54 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| AA23017PC23017-55 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| AA19821-8PC19821-55 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| AA21041PC19821-55 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| AA19819PC55 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| AA22052PC22052-55 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| AA19819-1PC54 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| AA2050PC22052-55 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
| AA23741PC23742-55 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
NSN 4820-00-326-6003 is a Diaphragm,valve,flat, manufactured by Hunt Valve Company, Inc., classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-00-326-6003 has 24 manufacturer part numbers on file: AA19821-8PC19821-55 (Hunt Valve Company, Inc.), AA19821-3PC19821-54 (Hunt Valve Company, Inc.), AA23178PC23178-54 (Hunt Valve Company, Inc.), AA20045PC20044-55 (Hunt Valve Company, Inc.), AA23148PC23148-55 (Hunt Valve Company, Inc.) and 19 more.
Key specifications for AA19821-8PC19821-55: Outside Diameter: 3.750 INCHES NOMINAL IN; Style Designator: FLAT; Material Thickness: 0.024 INCHES NOMINAL IN; Center Hole Diameter: 0.772 INCHES NOMINAL IN. 5 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.