The Valve,safety Relief, cataloged under National Stock Number 4820-01-466-3542, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Swagelok Co. 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-466-3542 |
| Primary Part Number | B-4CPA2-DR-50 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Swagelok Co |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Nominal Pipe Size Accommodated | 0.250 INCHES ALL ENDS IN |
| Connection Style | PLAIN (PIPE) ALL ENDS |
| Nominal Length | 1.620 INCHES ALL ENDS IN |
| Connection Type | THREADED EXTERNAL PIPE ALL ENDS |
| Style Designator | STRAIGHT THRU NOTE: TO BE USED FOR VALVE BODIES OF ONE SECTION ONLY. |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.250 INCHES ALL ENDS IN |
| Material | COPPER ALLOY BODY |
| Material | COPPER ALLOY FLOW CONTROL DEVICE |
| Thread Series Designator | NPT ALL ENDS |
| 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 |
|---|---|
| B-4CPA2-DR-50 PRIMARY | Swagelok Co (USA) |
| Reference | Meaning |
|---|---|
| B-4CPA2-DR-50 | 5/9 Secondary reference Nupro Co |
NSN 4820-01-466-3542 is a Valve,safety Relief, manufactured by Swagelok Co, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-466-3542 has 1 manufacturer part number on file: B-4CPA2-DR-50 (Swagelok Co).
1 possible match (shared part number, not a government interchangeability claim): 4820-01-511-5052. Verify interchangeability with system specifications before substitution.
Key specifications for B-4CPA2-DR-50: Flow Control Device: POPPET; Nominal Pipe Size Accommodated: 0.250 INCHES ALL ENDS IN; Connection Style: PLAIN (PIPE) ALL ENDS; Nominal Length: 1.620 INCHES ALL ENDS IN. 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.
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.