The Seat,valve, cataloged under National Stock Number 4820-01-145-9525, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is William E Williams Valve Corp. Government technical data includes 9 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 4820-01-145-9525 |
| Primary Part Number | CG810310F 3IN ITEM 3 |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | William E Williams Valve Corp |
| Status | ACTIVE |
| Thread Length | 0.435 INCHES NOMINAL SINGLE THREADED PORTION IN |
| Style Designator | PLAIN THREADED |
| Body Inside Diameter | 2.987 INCHES NOMINAL IN |
| Nominal Thread Size | 3.750 INCHES SINGLE THREADED PORTION IN |
| Thread Class | 2A SINGLE THREADED PORTION A |
| Thread Quantity Per Inch | 12 SINGLE THREADED PORTION |
| Material | STEEL OVERALL |
| Thread Series Designator | UN SINGLE THREADED PORTION |
| Seating Surface Shape | FLAT |
| 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 |
|---|---|
| CG810310F 3IN ITEM 3 PRIMARY | William E Williams Valve Corp (USA) |
| Reference | Meaning |
|---|---|
| CG810310F | D/9 Drawing number reference only William E Williams Valve Corp |
NSN 4820-01-145-9525 is a Seat,valve, manufactured by William E Williams Valve Corp, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-145-9525 has 1 manufacturer part number on file: CG810310F 3IN ITEM 3 (William E Williams Valve Corp).
1 possible match (shared part number, not a government interchangeability claim): 4820-01-145-9723. Verify interchangeability with system specifications before substitution.
Key specifications for CG810310F 3IN ITEM 3: Overall Height: 0.628 INCHES NOMINAL IN; Thread Length: 0.435 INCHES NOMINAL SINGLE THREADED PORTION IN; Style Designator: PLAIN THREADED; Body Inside Diameter: 2.987 INCHES NOMINAL IN. 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.