The Seat,valve, cataloged under National Stock Number 4820-01-236-5999, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is The Walworth Company. 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Item Name | Seat,valve |
| FSC / FSG | 4820 — Valves, Nonpowered (FSG 48) |
| Manufacturers | The Walworth Company (CAGE 63686) |
| Parameter | Value |
|---|---|
| NSN | 4820-01-236-5999 |
| Primary Part Number | A9777M113/628555 |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | The Walworth Company |
| Status | ACTIVE |
| 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 |
|---|---|
| A9777M113 3IN SEAT RING | The Walworth Company (USA) |
| A9777M113/628555 PRIMARY | The Walworth Company (USA) |
| Reference | Meaning |
|---|---|
| A9777M113 | D/9 Drawing number reference only The Walworth Company |
NSN 4820-01-236-5999 is a Seat,valve, manufactured by The Walworth Company, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-236-5999 has 2 manufacturer part numbers on file: A9777M113 3IN SEAT RING (The Walworth Company), A9777M113/628555 (The Walworth Company).
1 possible match (shared part number, not a government interchangeability claim): 4820-01-236-6099. Verify interchangeability with system specifications before substitution.
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.