The Valve,relief,pressure and Temper, cataloged under National Stock Number 4820-01-181-3565, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Watts Regulator Company. Government technical data includes 21 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. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-181-3565 |
| Primary Part Number | 40XL-4 |
| Item Name | Valve,relief,pressure and Temper |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Watts Regulator Company |
| Status | ACTIVE |
| Flow Control Device | BALL |
| First End Thread Direction | RIGHT-HAND |
| Temp Rating | 210.0 FAHRENHEIT DEGF |
| Second End Relationship with First End | NOT IDENTICAL |
| Body Style | SINGLE CONNECTION ANGLE FLOW |
| First End Style Designator | PLAIN |
| Bulb Length | 4.000 INCHES NOMINAL IN |
| Second End Nominal Pipe Size Accommodated | 1.315 INCHES IN |
| Material Document and Classification | 304, CRYOLAB DIV OF CRYENCO MFR REF SINGLE MATERIAL RESPONSE SEAT |
| End Connection Quantity | 2 |
| Second End Thread Direction | RIGHT-HAND |
| Second End Style Designator | PLAIN |
| First End Connection Type | THREADED EXTERNAL PIPE |
| Temp Adjustability | NOT ADJUSTABLE |
| Surface Treatment | COPPER ALLOY OUTSIDE |
| Test Data Document | 79227-MIL-V-136-12C SPECIFICATION (INCLUDES ENGINEERING TYPE BULLETINS, BROCHURES,ETC., THAT REFLECT SPECIFICATION TYPE DATA IN SPECIFICATION FORMAT; EXCLUDES COMMERCIAL CATALOGS, INDUSTRY DIRECTORIES, AND SIMILAR TRADE PUBLICATIONS, REFLECTING GENERAL TYPE DATA ON CERTAIN ENVIRONMENTAL AND PERFORMANCE REQUIREMENTS AND TEST CONDITIONS THAT ARE SHOWN AS "TYPICAL", "AVERAGE", "NOMINAL", ETC.). |
| First End Nominal Pipe Size Accommodated | 1.315 INCHES IN |
| Material | COPPER ALLOY BODY |
| Material | STEEL CORROSION RESISTING SEAT |
| Media for Which Designed | WATER, FRESH |
| Second End Connection Type | THREADED INTERNAL PIPE |
| 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 |
|---|---|
| 40XL-4 PRIMARY | Watts Regulator Company (USA) |
NSN 4820-01-181-3565 is a Valve,relief,pressure and Temper, manufactured by Watts Regulator Company, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-181-3565 has 1 manufacturer part number on file: 40XL-4 (Watts Regulator Company).
Key specifications for 40XL-4: Flow Control Device: BALL; First End Thread Direction: RIGHT-HAND; Temp Rating: 210.0 FAHRENHEIT DEGF; Second End Relationship with First End: NOT IDENTICAL. 21 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.