The Seat,valve, cataloged under National Stock Number 4820-01-442-9990, 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 11 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-442-9990 |
| Primary Part Number | 803-6397434-X52XXX-049L1 |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Naval Inventory Control Point Mechanicsburg |
| Status | ACTIVE |
| Flange Seat to Disk End Height | 0.216 INCHES NOMINAL IN |
| Flange Diameter | 2.117 INCHES NOMINAL IN |
| Criticality Code Justification | ZZZY |
| Style Designator | THREADED FLANGED |
| Material Document and Classification | MIL-C-24252 MIL SPEC SINGLE MATERIAL RESPONSE OVERALL |
| Nominal Thread Size | 1.9375 INCHES SINGLE THREADED PORTION IN |
| Thread Class | 3A SINGLE THREADED PORTION A |
| Thread Quantity Per Inch | 18 SINGLE THREADED PORTION |
| Material | COBALT COMP 1 OVERALL |
| Thread Series Designator | UNS SINGLE THREADED PORTION |
| Reference Number Differentiating Characteristics | MATERIAL CONTROLLED IAW NAVSEA 0948-LP-045-7010 MATERIAL CONTROL STANDARD FOR LEVEL I ITEMS |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL Q — CCL Item — Commerce Control List |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | S |
| Part Number | Manufacturer |
|---|---|
| 803-6397434-X52XXX-049L1 | Naval Inventory Control Point Mechanicsburg (USA) |
| Reference | Meaning |
|---|---|
| 803-6397434-X52XXX-049 | 3/1 Design control — primary reference Naval Sea Systems Command |
NSN 4820-01-442-9990 is a Seat,valve, manufactured by Naval Inventory Control Point Mechanicsburg, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-442-9990 has 1 manufacturer part number on file: 803-6397434-X52XXX-049L1 (Naval Inventory Control Point Mechanicsburg).
Key specifications for 803-6397434-X52XXX-049L1: Flange Seat to Disk End Height: 0.216 INCHES NOMINAL IN; Flange Diameter: 2.117 INCHES NOMINAL IN; Criticality Code Justification: ZZZY; Style Designator: THREADED FLANGED. 11 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.
NSN 4820-01-442-9990 has DEMIL Code Q. Demilitarization may be required before disposal or transfer to non-military entities.
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.