The Seat,valve, cataloged under National Stock Number 4820-01-503-3551, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Leslie Controls, Inc. Dba Leslie Controls Inc. Government technical data includes 14 specifications, cited from the U.S. Government catalog. The record lists 2 manufacturer part numbers 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-503-3551 |
| Primary Part Number | 098210058 |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Leslie Controls, Inc. Dba Leslie Controls Inc |
| Status | ACTIVE |
| Flange Seat to Disk End Height | 0.180 INCHES NOMINAL IN |
| Flange Diameter | 1.462 INCHES NOMINAL IN |
| Thread Length | 0.4062 INCHES NOMINAL SINGLE THREADED PORTION IN |
| Style Designator | THREADED FLANGED |
| Material Document and Classification | ASTM-A276 TYPE 410 ASSN STD SINGLE MATERIAL RESPONSE SEAT |
| Body Inside Diameter | 0.7810 INCHES NOMINAL IN |
| Nominal Thread Size | 1.312 INCHES SINGLE THREADED PORTION IN |
| Under Flange Height | 0.3438 INCHES NOMINAL IN |
| Thread Class | 3 SINGLE THREADED PORTION |
| Thread Quantity Per Inch | 16 SINGLE THREADED PORTION |
| Material | STEEL COMP 410 SEAT |
| Seat Angle in Deg | 45.000 NOMINAL |
| Thread Series Designator | UNS SINGLE THREADED PORTION |
| Seating Surface Shape | ANGULAR |
| 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 |
|---|---|
| 12435N PC NO. 21 | Leslie Controls, Inc. Dba Leslie Controls Inc (USA) |
| 098210058 PRIMARY | Leslie Controls, Inc. Dba Leslie Controls Inc (USA) |
| Reference | Meaning |
|---|---|
| 12435N | D/9 Drawing number reference only Leslie Controls, Inc. Dba Leslie Controls Inc |
NSN 4820-01-503-3551 is a Seat,valve, manufactured by Leslie Controls, Inc. Dba Leslie Controls Inc, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-503-3551 has 2 manufacturer part numbers on file: 12435N PC NO. 21 (Leslie Controls, Inc. Dba Leslie Controls Inc), 098210058 (Leslie Controls, Inc. Dba Leslie Controls Inc).
2 possible matches (shared part number, not a government interchangeability claim): 4820-01-503-3556, 4820-01-503-8419. Verify interchangeability with system specifications before substitution.
Key specifications for 098210058: Flange Seat to Disk End Height: 0.180 INCHES NOMINAL IN; Flange Diameter: 1.462 INCHES NOMINAL IN; Thread Length: 0.4062 INCHES NOMINAL SINGLE THREADED PORTION IN; Style Designator: THREADED FLANGED. 14 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.