The Disk,valve, cataloged under National Stock Number 4820-01-443-7056, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Naval Sea Systems Command. Government technical data includes 7 specifications, cited from the U.S. Government catalog. The record lists 3 manufacturer part numbers 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-443-7056 |
| Primary Part Number | 218016053 |
| Item Name | Disk,valve |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Naval Sea Systems Command |
| Status | ACTIVE |
| Shank Diameter | 0.246 INCHES MINIMUM AND 0.248 INCHES MAXIMUM IN |
| Flange Seat to Disk End Height | 0.850 INCHES NOMINAL IN |
| Outside Diameter | 0.670 INCHES MINIMUM AND 0.690 INCHES MAXIMUM IN |
| Style Designator | POPPET |
| Material Document and Classification | QQ-S-763, CLASS 304, COND A FED SPEC SINGLE MATERIAL RESPONSE |
| Seat Angle | 45.0 DEGREES NOMINAL |
| Material | STEEL COMP 304 |
| 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 |
|---|---|
| 556-6406592-MRHF-A12 | Naval Sea Systems Command (USA) |
| 556-6406592-MRHF-B12 | Naval Sea Systems Command (USA) |
| 218016053 PRIMARY | Naval Sea Systems Command (USA) |
| Reference | Meaning |
|---|---|
| 566-6406592-MRHF-A12 | 5/9 Secondary reference Naval Sea Systems Command |
| 6406592 | D/9 Drawing number reference only Naval Sea Systems Command |
NSN 4820-01-443-7056 is a Disk,valve, manufactured by Naval Sea Systems Command, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-443-7056 has 3 manufacturer part numbers on file: 556-6406592-MRHF-A12 (Naval Sea Systems Command), 556-6406592-MRHF-B12 (Naval Sea Systems Command), 218016053 (Naval Sea Systems Command).
2 possible matches (shared part number, not a government interchangeability claim): 4820-01-443-8644, 4730-01-445-4036. Verify interchangeability with system specifications before substitution.
Key specifications for 218016053: Shank Diameter: 0.246 INCHES MINIMUM AND 0.248 INCHES MAXIMUM IN; Flange Seat to Disk End Height: 0.850 INCHES NOMINAL IN; Overall Height: 0.940 INCHES NOMINAL IN; Outside Diameter: 0.670 INCHES MINIMUM AND 0.690 INCHES MAXIMUM IN. 7 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.