The Valve,safety Relief, cataloged under National Stock Number 4820-01-486-5173, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Parker-Hannifin Corporation Dba Pneutronics Div Hydraulic Valve Division. Government technical data includes 15 specifications, cited from the U.S. Government catalog. The record lists 3 manufacturer part numbers 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-486-5173 |
| Primary Part Number | 665-6-6SS1 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Parker-Hannifin Corporation Dba Pneutronics Div Hydraulic Valve Division |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Renewable Seat Ring Type | PRESSED-IN |
| Minimum Operating Temp | -40.0 FAHRENHEIT DEGF |
| Connection Type | THREADED INTERNAL TUBE ALL ENDS |
| Style Designator | STRAIGHT THRU NOTE: TO BE USED FOR VALVE BODIES OF ONE SECTION ONLY. |
| Nominal Outside Diameter Tube Accommodated | 0.250 INCHES ALL ENDS IN |
| Adjustable Pressure Range | +430.0 TO 650.0 POUNDS PER SQUARE INCH LBS |
| Disk Loading Method | SPRING |
| Media for Which Designed | ETHYLENE GLYCOL SINGLE RESPONSE |
| Material | STEEL COMP 416 FLOW CONTROL DEVICE |
| Material | RUBBER BUTADIENE-ACRYLONITRILE CLASS NBR SEAT |
| Material | STEEL CORROSION RESISTING BODY |
| Opening Pressure Setting | 550.0 POUNDS PER SQUARE INCH LBS |
| Valve Discharge Flow Rate | 4.0 GALLONS PER MINUTE |
| Valve Operation Method | AUTOMATIC |
| 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 |
|---|---|
| 23059486-6 | Rolls-Royce Corporation (USA) |
| 23059421 ITEM 80 | Rolls-Royce Corporation (USA) |
| 665-6-6SS1 PRIMARY | Parker-Hannifin Corporation Dba Pneutronics Div Hydraulic Valve Division (USA) |
| Reference | Meaning |
|---|---|
| 665-6-6SS1 | 5/9 Secondary reference U.S. Government activity |
| 665-6-6SS1 | C/1 Advisory reference — outside the item-of-supply concept Curtiss-Wright Flow Control Corporation Dba Farris Engineering Div Curtiss-Wright Valves Division- Farris |
NSN 4820-01-486-5173 is a Valve,safety Relief, manufactured by Parker-Hannifin Corporation Dba Pneutronics Div Hydraulic Valve Division, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-486-5173 has 3 manufacturer part numbers on file: 23059486-6 (Rolls-Royce Corporation), 23059421 ITEM 80 (Rolls-Royce Corporation), 665-6-6SS1 (Parker-Hannifin Corporation Dba Pneutronics Div Hydraulic Valve Division).
Key specifications for 665-6-6SS1: Flow Control Device: POPPET; Renewable Seat Ring Type: PRESSED-IN; Minimum Operating Temp: -40.0 FAHRENHEIT DEGF; Connection Type: THREADED INTERNAL TUBE ALL ENDS. 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.
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.