The Seat,valve, cataloged under National Stock Number 4820-01-486-8491, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Mission Systems Orchard Park Inc. Government technical data includes 2 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government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 | 4820-01-486-8491 |
| Primary Part Number | 1970-502-303-1 |
| Item Name | Seat,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Mission Systems Orchard Park Inc |
| Status | ACTIVE |
| Material Document and Classification | MIL-P-46036 MIL STD SINGLE MATERIAL RESPONSE SEAT |
| Material | PLASTIC POLYTETRAFLUOROETHYLENE SEAT |
| 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 |
|---|---|
| 1970-502-303-1 PRIMARY | Mission Systems Orchard Park Inc (USA) |
| Reference | Meaning |
|---|---|
| 1970-502-303-1 | 5/9 Secondary reference Carleton Technologies Inc Div Tampa Facility |
| 1970-502-3-3 | D/9 Drawing number reference only Mission Systems Orchard Park Inc |
NSN 4820-01-486-8491 is a Seat,valve, manufactured by Mission Systems Orchard Park Inc, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-486-8491 has 1 manufacturer part number on file: 1970-502-303-1 (Mission Systems Orchard Park Inc).
2 possible matches (shared part number, not a government interchangeability claim): 4820-01-574-2734, 2040-01-656-2615. Verify interchangeability with system specifications before substitution.
Key specifications for 1970-502-303-1: Material Document and Classification: MIL-P-46036 MIL STD SINGLE MATERIAL RESPONSE SEAT; Special Features: NEXT HIGHER ASSEMBLY VALVE, P/N B13385-1; End Item Identification: W/S DESIGNATOR LOS ANGELES CLASS SSN (688); Material: PLASTIC POLYTETRAFLUOROETHYLENE SEAT. 2 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.