The Seat,valve, cataloged under National Stock Number 4820-01-342-1731, 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 9 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-342-1731 |
| Primary Part Number | 73811-130/8543-009-440VM |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Naval Inventory Control Point Mechanicsburg |
| Status | ACTIVE |
| Flange Seat to Disk End Height | 0.937 INCHES NOMINAL IN |
| Flange Diameter | 4.895 INCHES NOMINAL IN |
| Body Outside Diameter | 4.500 INCHES NOMINAL IN |
| Style Designator | PLAIN FLANGED |
| Body Inside Diameter | 4.000 INCHES NOMINAL IN |
| Under Flange Height | 0.156 INCHES NOMINAL IN |
| Material | STEEL OVERALL |
| Reference Number Differentiating Characteristics | MAGNETIC PERMEABILITY SHALL NOT EXCEED 2.0 AFTER FABRICATION |
| Seating Surface Shape | O-RING |
| 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 |
|---|---|
| 73811-130/8543-009-440VM | Naval Inventory Control Point Mechanicsburg (USA) |
| 8543-009-440VM | Naval Inventory Control Point Mechanicsburg (USA) |
| Reference | Meaning |
|---|---|
| 8543-009-440VM | C/1 Advisory reference — outside the item-of-supply concept Velan Valve Corp. |
| 8543-009-440 | 3/1 Design control — primary reference Velan Valve Corp. |
| 73811-130/8543-009-440 | 5/1 Secondary reference Velan Valve Corp. |
NSN 4820-01-342-1731 is a Seat,valve, manufactured by Naval Inventory Control Point Mechanicsburg, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-342-1731 has 2 manufacturer part numbers on file: 73811-130/8543-009-440VM (Naval Inventory Control Point Mechanicsburg), 8543-009-440VM (Naval Inventory Control Point Mechanicsburg).
Key specifications for 73811-130/8543-009-440VM: Flange Seat to Disk End Height: 0.937 INCHES NOMINAL IN; Flange Diameter: 4.895 INCHES NOMINAL IN; Body Outside Diameter: 4.500 INCHES NOMINAL IN; Style Designator: PLAIN FLANGED. 9 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.