The Valve,safety Relief, cataloged under National Stock Number 4820-01-261-4128, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Hunt Valve Company, Inc.. Government technical data includes 30 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog.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 | 4820-01-261-4128 |
| Primary Part Number | R10AL5L506-CS4 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Hunt Valve Company, Inc. |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Flange Shape | ROUND WITH HOLES ALL ENDS |
| Furnished Items and Quantity | 1 LEVER |
| Flange Face Design | RAISED STRAIGHT ALL ENDS |
| Bolt Circle Nominal Diameter | 6.000 INCHES ALL ENDS IN |
| Connection Type | FLANGE ALL ENDS |
| Style Designator | ANGLE FLANGED ENDS |
| Material Document and Classification | QQ-N-281 FED SPEC SINGLE MATERIAL RESPONSE FLOW CONTROL DEVICE |
| Material Document and Classification | QQ-N-281 FED SPEC SINGLE MATERIAL RESPONSE SEAT |
| Material Document and Classification | ASTM B-61 ASSN STD SINGLE MATERIAL RESPONSE BODY |
| Material Document and Classification | ASTM A276 ASSN STD SINGLE MATERIAL RESPONSE STEM |
| Bolt Hole Nominal Diameter | 0.750 INCHES ALL ENDS IN |
| Operating Pressure | 150.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Valve Size | 3.000 INCHES IN |
| Adjustable Pressure Range | +18.0 TO 22.0 POUNDS PER SQUARE INCH LBS |
| Bonnet Type | INSIDE SCREW |
| Maximum Operating Temp | 250.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Second Connection Face to Centerline Distance | 5.062 INCHES IN |
| Nominal Outside Diameter | 7.500 INCHES ALL ENDS IN |
| Disk Loading Method | SPRING |
| Bolt Hole Quantity | 4 ALL ENDS |
| Bonnet Attachment Method | BOLTED |
| Media for Which Designed | WATER-OIL-GAS SINGLE RESPONSE |
| First Connection Face to Centerline Distance | 5.062 INCHES IN |
| Material | STEEL BODY |
| Material | NICKEL ALLOY FLOW CONTROL DEVICE |
| Material | NICKEL ALLOY SEAT |
| Material | STEEL CORROSION RESISTING STEM |
| Raised Face Nominal Diameter | 5.000 INCHES ALL ENDS IN |
| 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 |
|---|---|
| R10AL5L506-CS4 PRIMARY | Hunt Valve Company, Inc. (USA) |
| Reference | Meaning |
|---|---|
| R10AL5L506-CS4 | 3/9 Design control — primary reference Hunt Valve Company Inc Dba Union Flonetics |
NSN 4820-01-261-4128 is a Valve,safety Relief, manufactured by Hunt Valve Company, Inc., classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-261-4128 has 1 manufacturer part number on file: R10AL5L506-CS4 (Hunt Valve Company, Inc.).
Key specifications for R10AL5L506-CS4: Flow Control Device: DISK; Flange Shape: ROUND WITH HOLES ALL ENDS; Furnished Items and Quantity: 1 LEVER; Flange Face Design: RAISED STRAIGHT ALL ENDS. 30 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.