The Valve,check, cataloged under National Stock Number 4820-01-554-8679, 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 4 specifications, cited from the U.S. Government catalog. The record lists 2 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-554-8679 |
| Primary Part Number | SD-3-MN 3/8IN |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Watts Regulator Company |
| Status | ACTIVE |
| Valve Size | 0.375 INCHES IN |
| Face to Face Distance | 1.875 INCHES IN |
| Material | STEEL COMP 316 BODY |
| 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 |
|---|---|
| 3/8 SD-3-MN | Watts Regulator Company (USA) |
| SD-3-MN 3/8IN PRIMARY | Watts Regulator Company (USA) |
| Reference | Meaning |
|---|---|
| SD-3-MN | 5/1 Secondary reference Watts Regulator Company |
NSN 4820-01-554-8679 is a Valve,check, manufactured by Watts Regulator Company, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-554-8679 has 2 manufacturer part numbers on file: 3/8 SD-3-MN (Watts Regulator Company), SD-3-MN 3/8IN (Watts Regulator Company).
Key specifications for SD-3-MN 3/8IN: Valve Size: 0.375 INCHES IN; Special Features: DUAL CHECK WITH ATMOSPHERIC PORT DESIGNED FOR THE PROTECTION OF THE WATER SUPPLY FROM CARBON DIOXIDE GAS AND CARBONATED WATER; Face to Face Distance: 1.875 INCHES IN; Part Name Assigned by Controlling Agency: BACKFLOW PREVENTER WATTS SD-3. 4 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.