The Valve,safety Relief, cataloged under National Stock Number 4820-01-171-4393, 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 26 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-171-4393 |
| Primary Part Number | R10AH2H212 59T72PSI D49916 |
| 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 | PLAIN ALL ENDS |
| Bolt Circle Nominal Diameter | 3.875 INCHES ALL ENDS IN |
| Connection Type | FLANGE ALL ENDS |
| Style Designator | ANGLE FLANGED ENDS |
| Bolt Hole Nominal Diameter | 0.625 INCHES ALL ENDS IN |
| Operating Pressure | 300.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Valve Size | 1.500 INCHES IN |
| Adjustable Pressure Range | +59.0 TO 72.0 POUNDS PER SQUARE INCH LBS |
| Bonnet Type | INSIDE SCREW |
| Maximum Operating Temp | 250.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Second Connection Face to Centerline Distance | 4.750 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 |
| First Connection Face to Centerline Distance | 4.750 INCHES IN |
| Material | COPPER ALLOY BODY |
| Material | NICKEL ALLOY FLOW CONTROL DEVICE |
| Material | NICKEL ALLOY SEAT |
| Material | STEEL CORROSION RESISTING STEM |
| Opening Pressure Setting | 72.0 POUNDS PER SQUARE INCH LBS |
| Valve Operation Method | AUTOMATIC |
| Nominal Thickness | 0.437 INCHES ALL ENDS IN |
| 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 |
|---|---|
| R10AH2H212 | Hunt Valve Company, Inc. (USA) |
| R10AH2H212 59T72PSI D49916 PRIMARY | Hunt Valve Company, Inc. (USA) |
| Reference | Meaning |
|---|---|
| D49918 | D/9 Drawing number reference only Hunt Valve Company Inc Dba Union Flonetics |
| R10AH2H212 59T72PSI D49916 | 3/9 Design control — primary reference Hunt Valve Company Inc Dba Union Flonetics |
| R10AH2H212 | 5/9 Secondary reference Hunt Valve Company Inc Dba Union Flonetics |
NSN 4820-01-171-4393 is a Valve,safety Relief, manufactured by Hunt Valve Company, Inc., classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-171-4393 has 2 manufacturer part numbers on file: R10AH2H212 (Hunt Valve Company, Inc.), R10AH2H212 59T72PSI D49916 (Hunt Valve Company, Inc.).
2 possible matches (shared part number, not a government interchangeability claim): 4820-01-195-8424, 4820-01-316-4569. Verify interchangeability with system specifications before substitution.
Key specifications for R10AH2H212 59T72PSI D49916: Flow Control Device: DISK; Flange Shape: ROUND WITH HOLES ALL ENDS; Furnished Items and Quantity: 1 LEVER; Flange Face Design: PLAIN ALL ENDS. 26 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.