The Seat,valve, cataloged under National Stock Number 4820-01-520-3963, 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 8 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government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 | 4820-01-520-3963 |
| Primary Part Number | N816510058 |
| 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 | 0.187 INCHES NOMINAL IN |
| Body Outside Diameter | 1.624 INCHES NOMINAL IN |
| Style Designator | PLAIN FLANGED |
| Body Inside Diameter | 1.375 INCHES NOMINAL IN |
| Taper Length | 0.046 INCHES MAXIMUM IN |
| Material | STEEL CORROSION RESISTING OVERALL |
| Seat Angle in Deg | 45.000 NOMINAL |
| 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 |
|---|---|
| N816510058 PRIMARY | Leslie Controls, Inc. Dba Leslie Controls Inc (USA) |
| 35705N P/N 4A: N816510058 | Leslie Controls, Inc. Dba Leslie Controls Inc (USA) |
| Reference | Meaning |
|---|---|
| 18356N | D/9 Drawing number reference only Leslie Controls, Inc. Dba Leslie Controls Inc |
| 35705N | D/9 Drawing number reference only Leslie Controls, Inc. Dba Leslie Controls Inc |
NSN 4820-01-520-3963 is a Seat,valve, manufactured by Leslie Controls, Inc. Dba Leslie Controls Inc, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-520-3963 has 2 manufacturer part numbers on file: N816510058 (Leslie Controls, Inc. Dba Leslie Controls Inc), 35705N P/N 4A: N816510058 (Leslie Controls, Inc. Dba Leslie Controls Inc).
2 possible matches (shared part number, not a government interchangeability claim): 4810-01-520-8520, 4810-01-520-8521. Verify interchangeability with system specifications before substitution.
Key specifications for N816510058: Flange Seat to Disk End Height: 0.187 INCHES NOMINAL IN; Body Outside Diameter: 1.624 INCHES NOMINAL IN; Style Designator: PLAIN FLANGED; Body Inside Diameter: 1.375 INCHES NOMINAL IN. 8 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.