The Seat,valve, cataloged under National Stock Number 4820-01-640-7456, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Naval Inventory Control Point Mechanicsburg. Government technical data includes 2 specifications, cited from the U.S. Government catalog. The record lists 19 manufacturer part numbers for this item, enabling identification through both NSN and commercial part number lookups. 19 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 4820-01-640-7456 |
| Primary Part Number | CD-023-21-5D0 |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Naval Inventory Control Point Mechanicsburg |
| Status | ACTIVE |
| Criticality Code Justification | ZZZY |
| Reference Number Differentiating Characteristics | MATERIAL CONTROLLED IAW SS800-AG-MAN-010/P9290 SYSTEM CERTIFICATION PROCEDURES AND CRITERIA MANUAL FOR DEEP SUBMERGENCE SYSTEMS AND REQUIRES CLEANING, PACKING, AND MARKING IAW MIL-STD-1622 OR MIL-STD-1330 AS DEEMED APPLICABLE; CRITICAL ITEM FOR SAFETY AND SURVIVAL OF DEEP SUBMERGENCE RESEARCH AND RESCUE VEHICALS AS DIFFERENTIATED BY SPECIAL TEST FEATURES |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | S |
| Part Number | Manufacturer |
|---|---|
| CD-023-21-5D0 | Naval Inventory Control Point Mechanicsburg (USA) |
| PLC-12310 PC 4D0 | Naval Inventory Control Point Mechanicsburg (USA) |
| G547-0002-PLC-10373-5D0 | Naval Inventory Control Point Mechanicsburg (USA) |
| G547-0002-PLC-11401-005D0 | Naval Inventory Control Point Mechanicsburg (USA) |
| PLC-11401 PC 5D0 | Naval Inventory Control Point Mechanicsburg (USA) |
| CD-023-27-5D0 | Naval Inventory Control Point Mechanicsburg (USA) |
| 025461DCD0 | Naval Inventory Control Point Mechanicsburg (USA) |
| CD-023-22-5D0 | Naval Inventory Control Point Mechanicsburg (USA) |
| H547-0001-PLC-11401-005D0 | Naval Inventory Control Point Mechanicsburg (USA) |
| 7383858-PLC-11403-5D0 | Naval Inventory Control Point Mechanicsburg (USA) |
| H547-0001-PLC-11403-5D0 | Naval Inventory Control Point Mechanicsburg (USA) |
| CD-023-29-5D0 | Naval Inventory Control Point Mechanicsburg (USA) |
| CD-023-40-5D0 | Naval Inventory Control Point Mechanicsburg (USA) |
| CD-023-31-4D0 | Naval Inventory Control Point Mechanicsburg (USA) |
| 7383858-PLC-11401-005D0 | Naval Inventory Control Point Mechanicsburg (USA) |
| 7550478-PLC-10373-5D0 | Naval Inventory Control Point Mechanicsburg (USA) |
| PLC-10373 ITEM 5D0 | Naval Inventory Control Point Mechanicsburg (USA) |
| PLC-11403 PC 5D0 | Naval Inventory Control Point Mechanicsburg (USA) |
| 7550478-PLC-11401-005D0 | Naval Inventory Control Point Mechanicsburg (USA) |
| Reference | Meaning |
|---|---|
| G547-0002-PLC-10373-5 | 5/1 Secondary reference U.S. Government activity |
| H547-0001-PLC-11401-005 | 5/1 Secondary reference U.S. Government activity |
| CD-023-29-5 | 5/1 Secondary reference Naval Sea Systems Command |
| PLC-10373 ITEM 5 | 5/1 Secondary reference U.S. Government activity |
| PLC-11403 PC 5 | 5/1 Secondary reference U.S. Government activity |
| H547-0001-PLC-11403-5 | 5/1 Secondary reference U.S. Government activity |
| CD-023-31-4 | 5/1 Secondary reference Naval Sea Systems Command |
| 7383858-PLC-11403-5 | 5/1 Secondary reference Naval Sea Systems Command |
| 7550478-PLC-10373-5 | 5/1 Secondary reference Naval Sea Systems Command |
| PLC-11401 PC 5 | 5/1 Secondary reference U.S. Government activity |
| 025461DC | 3/1 Design control — primary reference U.S. Government activity |
| PLC-12310 PC 4 | 5/1 Secondary reference U.S. Government activity |
| CD-023-21-5 | 5/1 Secondary reference Naval Sea Systems Command |
| CD-023-40-5 | 5/1 Secondary reference Naval Sea Systems Command |
| CD-023-27-5 | 5/1 Secondary reference Naval Sea Systems Command |
| G547-0002-PLC-11401-005 | 5/1 Secondary reference U.S. Government activity |
| 7550478-PLC-11401-005 | 5/1 Secondary reference Naval Sea Systems Command |
| 7383858-PLC-11401-005 | 5/1 Secondary reference Naval Sea Systems Command |
| CD-023-22-5 | 5/1 Secondary reference Naval Sea Systems Command |
NSN 4820-01-640-7456 is a Seat,valve, manufactured by Naval Inventory Control Point Mechanicsburg, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-640-7456 has 19 manufacturer part numbers on file: CD-023-21-5D0 (Naval Inventory Control Point Mechanicsburg), PLC-12310 PC 4D0 (Naval Inventory Control Point Mechanicsburg), G547-0002-PLC-10373-5D0 (Naval Inventory Control Point Mechanicsburg), G547-0002-PLC-11401-005D0 (Naval Inventory Control Point Mechanicsburg), PLC-11401 PC 5D0 (Naval Inventory Control Point Mechanicsburg) and 14 more.
1 possible match (shared part number, not a government interchangeability claim): 4820-01-687-0895. Verify interchangeability with system specifications before substitution.
Key specifications for CD-023-21-5D0: Criticality Code Justification: ZZZY; Reference Number Differentiating Characteristics: MATERIAL CONTROLLED IAW SS800-AG-MAN-010/P9290 SYSTEM CERTIFICATION PROCEDURES AND CRITERIA MANUAL FOR DEEP SUBMERGENCE SYSTEMS AND REQUIRES CLEANING, PACKING, AND MARKING IAW MIL-STD-1622 OR MIL-STD-1330 AS DEEMED APPLICABLE; CRITICAL ITEM FOR SAFETY AND SURVIVAL OF DEEP SUBMERGENCE RESEARCH AND RESCUE VEHICALS AS DIFFERENTIATED BY SPECIAL TEST FEATURES. 2 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.