The Valve,butterfly, cataloged under National Stock Number 4820-01-377-6647, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Thomas Willcox Co, Inc. Government technical data includes 10 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-377-6647 |
| Primary Part Number | 911L561 |
| Item Name | Valve,butterfly |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Thomas Willcox Co, Inc |
| Status | ACTIVE |
| Connection Type | FLANGE ALL ENDS |
| Style Designator | STRAIGHT THRU FLANGED ENDS |
| Valve Size | 10.000 INCHES IN |
| Features Provided | MANUAL OVERRIDE |
| Mounting Facility | BRACKET(S) |
| Face to Face Distance | 9.380 INCHES IN |
| Material | RUBBER BUTADIENE-ACRYLONITRILE CLASS NBR SEAT |
| Material | ALUMINUM ALLOY BODY |
| Material | COPPER ALLOY 630 FLOW CONTROL DEVICE |
| Valve Operation Method | MANUAL |
| 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 |
|---|---|
| 911L561 | Thomas Willcox Co, Inc (USA) |
| Reference | Meaning |
|---|---|
| 911L561 | 3/9 Design control — primary reference U.S. Government activity |
NSN 4820-01-377-6647 is a Valve,butterfly, manufactured by Thomas Willcox Co, Inc, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-377-6647 has 1 manufacturer part number on file: 911L561 (Thomas Willcox Co, Inc).
Key specifications for 911L561: Connection Type: FLANGE ALL ENDS; Style Designator: STRAIGHT THRU FLANGED ENDS; Valve Size: 10.000 INCHES IN; Features Provided: MANUAL OVERRIDE. 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.