The Valve,check, cataloged under National Stock Number 4820-01-246-4557, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Naval Inventory Control Point Mechanicsburg. 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through both NSN and commercial part number lookups. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-246-4557 |
| Primary Part Number | M-8C4-1CP |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Naval Inventory Control Point Mechanicsburg |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Connection Style | PLAIN, OPTIONAL END (PIPE) ALL ENDS |
| Mounting Position | HORIZONTAL OR VERTICAL |
| Criticality Code Justification | ZZZY |
| Connection Type | THREADED INTERNAL PIPE ALL ENDS |
| Style Designator | STRAIGHT THRU |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.500 INCHES ALL ENDS IN |
| Disk Loading Method | SPRING |
| Material | NICKEL ALLOY FLOW CONTROL DEVICE |
| Material | NICKEL ALLOY BODY |
| Thread Series Designator | NPT ALL ENDS |
| Opening Pressure Setting | 1.0 POUNDS PER SQUARE INCH LBS |
| Valve Operation Method | AUTOMATIC |
| Reference Number Differentiating Characteristics | CLEANING, PACKAGING, AND MARKING IAW THE LATEST REVISION OF MIL-STD-1330 |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | S |
| Part Number | Manufacturer |
|---|---|
| M-8C4-1CP | Naval Inventory Control Point Mechanicsburg (USA) |
| Reference | Meaning |
|---|---|
| M-8C4-1 | 3/1 Design control — primary reference Swagelok Co |
| M-8C4-1 | 5/9 Secondary reference Nupro Co |
NSN 4820-01-246-4557 is a Valve,check, manufactured by Naval Inventory Control Point Mechanicsburg, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-246-4557 has 1 manufacturer part number on file: M-8C4-1CP (Naval Inventory Control Point Mechanicsburg).
Key specifications for M-8C4-1CP: Flow Control Device: POPPET; Connection Style: PLAIN, OPTIONAL END (PIPE) ALL ENDS; Mounting Position: HORIZONTAL OR VERTICAL; Criticality Code Justification: ZZZY. 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.