The Valve,safety Relief, cataloged under National Stock Number 4820-01-211-5100, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Ministry of Defence, De&s Air Defence Electronic Warfare Systems (adews Dt). Government technical data includes 18 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 4820-01-211-5100 |
| Primary Part Number | 559T2MP7 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Ministry of Defence, De&s Air Defence Electronic Warfare Systems (adews Dt) |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Connection Style | PLAIN,OPTIONAL END(PIPE) SECOND END |
| Connection Style | PLAIN (PIPE) FIRST END |
| Connection Type | THREADED INTERNAL PIPE SECOND END |
| Connection Type | THREADED EXTERNAL PIPE FIRST END |
| Style Designator | STRAIGHT THRU NOTE: TO BE USED FOR VALVE BODIES OF ONE SECTION ONLY. |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.250 INCHES ALL ENDS IN |
| Media for Which Designed | ACETYLENE SECOND RESPONSE |
| Media for Which Designed | HYDROGEN FIFTH RESPONSE |
| Media for Which Designed | AMMONIA, GASEOUS THIRD RESPONSE |
| Media for Which Designed | AIR FIRST RESPONSE |
| Media for Which Designed | REFRIGERANT 12 FOURTH RESPONSE |
| Material | RUBBER BUTADIENE-ACRYLONITRILE CLASS NBR SEAT |
| Material | STEEL COMP 303 BODY |
| Thread Series Designator | NPT ALL ENDS |
| Opening Pressure Setting | 7.0 POUNDS PER SQUARE INCH LBS |
| Valve Operation Method | AUTOMATIC |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL Q — CCL Item — Commerce Control List |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| 559T2MP7 | Ministry of Defence, De&s Air Defence Electronic Warfare Systems (adews Dt) (GBR) |
| Reference | Meaning |
|---|---|
| 559T-2MP-7 | 3/2 Design control — primary reference U.S. Government activity |
NSN 4820-01-211-5100 is a Valve,safety Relief, manufactured by Ministry of Defence, De&s Air Defence Electronic Warfare Systems (adews Dt), classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-211-5100 has 1 manufacturer part number on file: 559T2MP7 (Ministry of Defence, De&s Air Defence Electronic Warfare Systems (adews Dt)).
Key specifications for 559T2MP7: Flow Control Device: POPPET; Connection Style: PLAIN,OPTIONAL END(PIPE) SECOND END; Connection Style: PLAIN (PIPE) FIRST END; Connection Type: THREADED INTERNAL PIPE SECOND END. 18 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 4820-01-211-5100 has DEMIL Code Q. 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.