The Seat,valve, cataloged under National Stock Number 4820-01-221-7338, 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 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 4820-01-221-7338 |
| Primary Part Number | 152F ITEM 6 |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | William E Williams Valve Corp |
| Status | ACTIVE |
| Flange Seat to Disk End Height | 0.185 INCHES MINIMUM AND 0.375 INCHES MAXIMUM IN |
| Flange Diameter | 1.635 INCHES NOMINAL IN |
| Thread Length | 0.170 INCHES NOMINAL SINGLE THREADED PORTION IN |
| Style Designator | THREADED FLANGED |
| Body Inside Diameter | 1.025 INCHES NOMINAL IN |
| Nominal Thread Size | 1.500 INCHES SINGLE THREADED PORTION IN |
| Under Flange Height | 0.250 INCHES NOMINAL IN |
| Thread Class | 3A SINGLE THREADED PORTION A |
| Material | COPPER ALLOY OVERALL |
| Thread Series Designator | UNEF 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 |
|---|---|
| 152F ITEM 6 PRIMARY | William E Williams Valve Corp (USA) |
| Reference | Meaning |
|---|---|
| 152F 4IN ITEM 6 | C/1 Advisory reference — outside the item-of-supply concept William E Williams Valve Corp |
NSN 4820-01-221-7338 is a Seat,valve, manufactured by William E Williams Valve Corp, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-221-7338 has 1 manufacturer part number on file: 152F ITEM 6 (William E Williams Valve Corp).
Key specifications for 152F ITEM 6: Flange Seat to Disk End Height: 0.185 INCHES MINIMUM AND 0.375 INCHES MAXIMUM IN; Flange Diameter: 1.635 INCHES NOMINAL IN; Thread Length: 0.170 INCHES NOMINAL SINGLE THREADED PORTION IN; 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.
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.