The Valve,safety Relief, cataloged under National Stock Number 4820-00-034-5877, 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 15 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-00-034-5877 |
| Primary Part Number | MC7543-1 |
| 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 | FLARED (TUBE) FIRST END |
| Style Designator | STRAIGHT THRU |
| Nominal Outside Diameter Tube Accommodated | 0.250 INCHES FIRST END IN |
| Operating Pressure | 290.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Thread Direction | RIGHT-HAND FIRST END |
| Nominal Thread Size | 0.437 INCHES FIRST END IN |
| Seat Angle | 37.0 DEGREES FIRST END |
| Disk Loading Method | SPRING |
| Media for Which Designed | AIR SINGLE RESPONSE |
| Thread Class | 3A FIRST END A |
| Thread Quantity Per Inch | 20 FIRST END |
| Thread Series Designator | UNF FIRST END |
| Opening Pressure Setting | 23.0 POUNDS PER SQUARE INCH LBS |
| 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 |
|---|---|
| MC7543-1 PRIMARY | Eaton Aerospace Llc Dba Sterer Engineering Div M.c.aerospace (USA) |
| Reference | Meaning |
|---|---|
| 53-720057-1 | 7/2 Vendor item drawing reference The Boeing Company Div Defense |
NSN 4820-00-034-5877 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 4820-00-034-5877 has 1 manufacturer part number on file: MC7543-1 (Eaton Aerospace Llc Dba Sterer Engineering Div M.c.aerospace).
Key specifications for MC7543-1: Flow Control Device: POPPET; Connection Style: FLARED (TUBE) FIRST END; Style Designator: STRAIGHT THRU; Nominal Outside Diameter Tube Accommodated: 0.250 INCHES FIRST END IN. 15 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 4820-00-034-5877 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.