The Valve,safety Relief, cataloged under National Stock Number 4820-00-435-7577, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Caterpillar Inc Div Caterpillar Defense. Government technical data includes 10 specifications, cited from the U.S. Government catalog. The record lists 7 manufacturer part numbers 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 5 items share a part number with this NSN in the catalog (possible match — not a government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 | 4820-00-435-7577 |
| Primary Part Number | 4-R-3249 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Caterpillar Inc Div Caterpillar Defense |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Connection Style | PLAIN,OPTIONAL END(PIPE) ALL ENDS |
| Connection Type | THREADED INTERNAL PIPE ALL ENDS |
| Style Designator | ANGLE |
| Operating Pressure | 75.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.250 INCHES ALL ENDS IN |
| Material | ALUMINUM OVERALL |
| Thread Series Designator | NPT ALL ENDS |
| 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 |
|---|---|
| 4-R-3249 PRIMARY | Caterpillar Inc Div Caterpillar Defense (USA) |
| 346-95 PRIMARY | Crane Carrier Company, Llc (USA) |
| 36Z571 | Morris Material Handling, Inc. (USA) |
| 277227 PRIMARY | Bendix Commercial Vehicle Systems Llc Dba Bendix Commercial Vehicle Systems (USA) |
| 051-00011 | Kovatch Corp. (USA) |
| 11621099 PRIMARY | U S Army Tank Automotive Command Amsta-Im-Mm (USA) |
| 277227N PRIMARY | Bendix Commercial Vehicle Systems Llc Dba Bendix Commercial Vehicle Systems (USA) |
| Reference | Meaning |
|---|---|
| 7-926-000931 | C/1 Advisory reference — outside the item-of-supply concept Keystone Automotive Operations Inc Dba Grove North America |
NSN 4820-00-435-7577 is a Valve,safety Relief, manufactured by Caterpillar Inc Div Caterpillar Defense, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-00-435-7577 has 7 manufacturer part numbers on file: 4-R-3249 (Caterpillar Inc Div Caterpillar Defense), 346-95 (Crane Carrier Company, Llc), 36Z571 (Morris Material Handling, Inc.), 277227 (Bendix Commercial Vehicle Systems Llc Dba Bendix Commercial Vehicle Systems), 051-00011 (Kovatch Corp.) and 2 more.
5 possible matches (shared part number, not a government interchangeability claim): 5910-00-921-8242, 5920-01-083-8654, 3220-01-198-3309. Verify interchangeability with system specifications before substitution.
Key specifications for 4-R-3249: Flow Control Device: DISK; Connection Style: PLAIN,OPTIONAL END(PIPE) ALL ENDS; Connection Type: THREADED INTERNAL PIPE ALL ENDS; Style Designator: ANGLE. 10 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.