The Diaphragm,valve,flat, cataloged under National Stock Number 4820-01-391-5907, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Senior Operations Llc Dba Metal Bellows Div Metal Bellows. Government technical data includes 6 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-391-5907 |
| Primary Part Number | 5186637 |
| Item Name | Diaphragm,valve,flat |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Senior Operations Llc Dba Metal Bellows Div Metal Bellows |
| Status | ACTIVE |
| Outside Diameter | 11.515 INCHES NOMINAL IN |
| Material Thickness | 2.875 INCHES NOMINAL IN |
| Bolt Hole Quantity | 12 |
| Bolt Circle Diameter | 10.400 INCHES NOMINAL IN |
| Center Hole Diameter | 0.875 INCHES NOMINAL IN |
| Hole Diameter | 0.240 INCHES NOMINAL 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 |
|---|---|
| 5186637 PRIMARY | Senior Operations Llc Dba Metal Bellows Div Metal Bellows (USA) |
| Reference | Meaning |
|---|---|
| 5186637 | 3/9 Design control — primary reference Senior Flexonics Inc |
| 5186637 | 7/2 Vendor item drawing reference Naval Sea Systems Command |
NSN 4820-01-391-5907 is a Diaphragm,valve,flat, manufactured by Senior Operations Llc Dba Metal Bellows Div Metal Bellows, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-391-5907 has 1 manufacturer part number on file: 5186637 (Senior Operations Llc Dba Metal Bellows Div Metal Bellows).
Key specifications for 5186637: Outside Diameter: 11.515 INCHES NOMINAL IN; Material Thickness: 2.875 INCHES NOMINAL IN; Bolt Hole Quantity: 12; Bolt Circle Diameter: 10.400 INCHES NOMINAL IN. 6 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.