The Valve,check, cataloged under National Stock Number 4820-01-331-3555, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is William E Williams Valve Corp. Government technical data includes 15 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 | 4820-01-331-3555 |
| Primary Part Number | 151F1-4IN |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | William E Williams Valve Corp |
| Status | ACTIVE |
| Flange Shape | ROUND WITH HOLES ALL ENDS |
| Flange Face Design | PLAIN ALL ENDS |
| Bolt Circle Nominal Diameter | 7.500 INCHES ALL ENDS IN |
| Mounting Position | HORIZONTAL |
| Supplementary Features | FLOW CONTROL DEVICE: DILATING O-RING |
| Connection Type | FLANGE ALL ENDS |
| Style Designator | STRAIGHT THRU |
| Bolt Hole Nominal Diameter | 0.625 INCHES ALL ENDS IN |
| Operating Pressure | 150.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Nominal Outside Diameter | 9.000 INCHES ALL ENDS IN |
| Bolt Hole Quantity | 8 ALL ENDS |
| Media for Which Designed | AIR SINGLE RESPONSE |
| Material | STEEL BODY |
| Valve Operation Method | AUTOMATIC |
| Nominal Thickness | 1.312 INCHES ALL ENDS IN |
| 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 |
|---|---|
| 151F1-4IN PRIMARY | William E Williams Valve Corp (USA) |
NSN 4820-01-331-3555 is a Valve,check, manufactured by William E Williams Valve Corp, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-331-3555 has 1 manufacturer part number on file: 151F1-4IN (William E Williams Valve Corp).
Key specifications for 151F1-4IN: Flange Shape: ROUND WITH HOLES ALL ENDS; Flange Face Design: PLAIN ALL ENDS; Bolt Circle Nominal Diameter: 7.500 INCHES ALL ENDS IN; Mounting Position: HORIZONTAL. 15 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.