The Disk,rupturable, cataloged under National Stock Number 4820-01-491-4870, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Johnson Controls Ltd, York Navy Systems. Government technical data includes 6 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-491-4870 |
| Primary Part Number | 268L64397-M00 |
| Item Name | Disk,rupturable |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Johnson Controls Ltd, York Navy Systems |
| Status | ACTIVE |
| Disk Material | COPPER |
| Burst Pressure | 235.0 PRESSURE POUNDS PER SQUARE INCH GAGE |
| Burst Temperature | 72.0 FAHRENHEIT DEGF |
| Disk Type | SOLID |
| Features Provided | NONFRAGMENTING |
| Disk Size | 0.500 INCHES 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 |
|---|---|
| 268L64397-M00 | Johnson Controls Ltd, York Navy Systems (GBR) |
| 426L64130-M00 ITEM 20 | Johnson Controls Ltd, York Navy Systems (GBR) |
| Reference | Meaning |
|---|---|
| 5525-235-CE | 5/9 Secondary reference Henry Technologies, Inc. |
| 5525-235 | 5/9 Secondary reference Henry Technologies, Inc. |
| 555-235-CE | 3/9 Design control — primary reference Henry Technologies, Inc. |
NSN 4820-01-491-4870 is a Disk,rupturable, manufactured by Johnson Controls Ltd, York Navy Systems, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-491-4870 has 2 manufacturer part numbers on file: 268L64397-M00 (Johnson Controls Ltd, York Navy Systems), 426L64130-M00 ITEM 20 (Johnson Controls Ltd, York Navy Systems).
Key specifications for 268L64397-M00: Disk Material: COPPER; Burst Pressure: 235.0 PRESSURE POUNDS PER SQUARE INCH GAGE; Burst Temperature: 72.0 FAHRENHEIT DEGF; Disk Type: SOLID. 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.