The Valve,check, cataloged under National Stock Number 4820-00-202-6819, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Derbyshire Machine & Tool 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 4820-00-202-6819 |
| Primary Part Number | B/MX5725 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Derbyshire Machine & Tool Co |
| Status | ACTIVE |
| Flow Control Device | DISK |
| Flange Shape | ROUND WITH HOLES FIRST END |
| Flange Face Design | PLAIN FIRST END |
| Mounting Position | HORIZONTAL |
| Connection Type | FLANGE FIRST END |
| Style Designator | STRAIGHT THRU |
| Operating Pressure | 500.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Nominal Outside Diameter | 4.250 INCHES FIRST END IN |
| Face to Face Distance | 5.875 INCHES IN |
| Media for Which Designed | WATER, SALT SINGLE RESPONSE |
| 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 |
|---|---|
| B/MX5725 | Derbyshire Machine & Tool Co (USA) |
| Reference | Meaning |
|---|---|
| S4824-313854 | 3/2 Design control — primary reference U.S. Government activity |
| 3600-137 | 3/2 Design control — primary reference U.S. Government activity |
NSN 4820-00-202-6819 is a Valve,check, manufactured by Derbyshire Machine & Tool Co, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-00-202-6819 has 1 manufacturer part number on file: B/MX5725 (Derbyshire Machine & Tool Co).
1 possible match (shared part number, not a government interchangeability claim): 1560-00-613-8113. Verify interchangeability with system specifications before substitution.
Key specifications for B/MX5725: Flow Control Device: DISK; Flange Shape: ROUND WITH HOLES FIRST END; Flange Face Design: PLAIN FIRST END; Mounting Position: HORIZONTAL. 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.