The Valve,safety Relief, cataloged under National Stock Number 4820-01-425-2894, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is D & D Instruments Inc. Government technical data includes 11 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Cancelled.
| Parameter | Value |
|---|---|
| NSN | 4820-01-425-2894 |
| Primary Part Number | 995253 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | D & D Instruments Inc |
| Status | CANCELLED |
| Connection Style | PLAIN (PIPE) ALL ENDS |
| Connection Type | THREADED EXTERNAL PIPE ALL ENDS |
| Style Designator | ANGLE |
| Operating Pressure | 300.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.250 INCHES ALL ENDS IN |
| Maximum Operating Temp | 250.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Material | COPPER ALLOY BODY |
| Thread Series Designator | NPT ALL ENDS |
| Opening Pressure Setting | 150.0 POUNDS PER SQUARE INCH LBS |
| Valve Operation Method | AUTOMATIC |
| Acquisition Status | CANCELLED |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| 995253 PRIMARY | D & D Instruments Inc (USA) |
| Reference | Meaning |
|---|---|
| 18152 | 3/9 Design control — primary reference Horton Industries Inc |
NSN 4820-01-425-2894 is a Valve,safety Relief, manufactured by D & D Instruments Inc, classified under FSC 4820, Valves, Nonpowered. Status: cancelled.
NSN 4820-01-425-2894 has 1 manufacturer part number on file: 995253 (D & D Instruments Inc).
1 possible match (shared part number, not a government interchangeability claim): 4130-01-471-6116. Verify interchangeability with system specifications before substitution.
Key specifications for 995253: Connection Style: PLAIN (PIPE) ALL ENDS; Connection Type: THREADED EXTERNAL PIPE ALL ENDS; Style Designator: ANGLE; Operating Pressure: 300.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS. 11 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 4820-01-425-2894 is currently cancelled. Check with the Defense Logistics Agency for current availability and authorized substitutes.
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.