The Seat,valve, cataloged under National Stock Number 4820-01-212-5259, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Eaton Aerospace Llc. 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 | 4820-01-212-5259 |
| Primary Part Number | 27641 |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Eaton Aerospace Llc |
| Status | ACTIVE |
| Flange Seat to Disk End Height | 0.1315 INCHES NOMINAL IN |
| Flange Diameter | 0.419 INCHES MINIMUM AND 0.420 INCHES MAXIMUM IN |
| FSC Application Data | ACFT ENG FUEL SYSTEM COMPONENTS |
| Body Outside Diameter | 0.309 INCHES MINIMUM AND 0.310 INCHES MAXIMUM IN |
| Hardness Rating | 38.0 ROCKWELL C MINIMUM AND 45.0 ROCKWELL C MAXIMUM OVERALL |
| Style Designator | PLAIN FLANGED |
| Material Document and Classification | AMS5643 ASSN STD SINGLE MATERIAL RESPONSE OVERALL |
| Body Inside Diameter | 0.187 INCHES NOMINAL IN |
| Surface Treatment | PASSIVATE OVERALL |
| Under Flange Height | 0.099 INCHES NOMINAL IN |
| Material | STEEL COMP 17-4PH OVERALL |
| 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 |
|---|---|
| 27641 PRIMARY | Eaton Aerospace Llc (USA) |
NSN 4820-01-212-5259 is a Seat,valve, manufactured by Eaton Aerospace Llc, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-212-5259 has 1 manufacturer part number on file: 27641 (Eaton Aerospace Llc).
Key specifications for 27641: Flange Seat to Disk End Height: 0.1315 INCHES NOMINAL IN; Flange Diameter: 0.419 INCHES MINIMUM AND 0.420 INCHES MAXIMUM IN; FSC Application Data: ACFT ENG FUEL SYSTEM COMPONENTS; Body Outside Diameter: 0.309 INCHES MINIMUM AND 0.310 INCHES MAXIMUM IN. 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.