The Seat,valve, cataloged under National Stock Number 4820-01-203-7641, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is O. C. Keckley Company. Government technical data includes 12 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. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-203-7641 |
| Primary Part Number | 17552-A |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | O. C. Keckley Company |
| Status | ACTIVE |
| Flange Seat to Disk End Height | 0.375 INCHES NOMINAL IN |
| Flange Diameter | 3.438 INCHES NOMINAL IN |
| Thread Length | 0.750 INCHES NOMINAL SINGLE THREADED PORTION IN |
| Style Designator | THREADED FLANGED |
| Body Inside Diameter | 2.750 INCHES MINIMUM AND 2.752 INCHES MAXIMUM IN |
| Nominal Thread Size | 3.250 INCHES SINGLE THREADED PORTION IN |
| Under Flange Height | 0.750 INCHES NOMINAL IN |
| Thread Class | 2A SINGLE THREADED PORTION A |
| Thread Quantity Per Inch | 16 SINGLE THREADED PORTION |
| Material | COPPER ALLOY OVERALL |
| Thread Series Designator | UNS 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 |
|---|---|
| 17552-A PRIMARY | O. C. Keckley Company (USA) |
NSN 4820-01-203-7641 is a Seat,valve, manufactured by O. C. Keckley Company, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-203-7641 has 1 manufacturer part number on file: 17552-A (O. C. Keckley Company).
Key specifications for 17552-A: Flange Seat to Disk End Height: 0.375 INCHES NOMINAL IN; Flange Diameter: 3.438 INCHES NOMINAL IN; Thread Length: 0.750 INCHES NOMINAL SINGLE THREADED PORTION IN; Style Designator: THREADED FLANGED. 12 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.