The Valve,safety Relief, cataloged under National Stock Number 4820-00-083-1250, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Eaton Aerospace Llc Dba Sterer Engineering Div M.c.aerospace. Government technical data includes 9 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-083-1250 |
| Primary Part Number | MC5209 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Eaton Aerospace Llc Dba Sterer Engineering Div M.c.aerospace |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Connection Style | GASKET SEAL(BOSS) ALL ENDS |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Maximum Operating Temp | 275.0 FAHRENHEIT SECOND RESPONSE DEGF |
| Maximum Operating Temp | -65.0 FAHRENHEIT FIRST RESPONSE DEGF |
| Disk Loading Method | SPRING |
| Thread Class | 3B ALL ENDS |
| Valve Discharge Flow Rate | 16.0 GALLONS PER MINUTE |
| Valve Operation Method | AUTOMATIC |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL B — Remove Demilitarization Key Points |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| 128SCH131-1 | Northrop Grumman Systems Corporation (USA) |
| MC5209 PRIMARY | Eaton Aerospace Llc Dba Sterer Engineering Div M.c.aerospace (USA) |
| Reference | Meaning |
|---|---|
| 128SCH131-1 | 5/9 Secondary reference Northrop Grumman Systems Corporation |
NSN 4820-00-083-1250 is a Valve,safety Relief, manufactured by Eaton Aerospace Llc Dba Sterer Engineering Div M.c.aerospace, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-00-083-1250 has 2 manufacturer part numbers on file: 128SCH131-1 (Northrop Grumman Systems Corporation), MC5209 (Eaton Aerospace Llc Dba Sterer Engineering Div M.c.aerospace).
1 possible match (shared part number, not a government interchangeability claim): 4820-00-225-0977. Verify interchangeability with system specifications before substitution.
Key specifications for MC5209: Flow Control Device: POPPET; Connection Style: GASKET SEAL(BOSS) ALL ENDS; Thread Direction: RIGHT-HAND ALL ENDS; Maximum Operating Temp: 275.0 FAHRENHEIT SECOND RESPONSE DEGF. 9 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.
NSN 4820-00-083-1250 has DEMIL Code B. Demilitarization may be required before disposal or transfer to non-military entities.
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.