The Valve,check, cataloged under National Stock Number 4820-01-407-2965, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Parker-Hannifin Corporation Dba Pneutronics Div Hydraulic Valve Division. Government technical data includes 18 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-407-2965 |
| Primary Part Number | CS-800-S-20-V |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Parker-Hannifin Corporation Dba Pneutronics Div Hydraulic Valve Division |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Connection Style | FLARE (TUBE) ALL ENDS |
| Mounting Position | HORIZONTAL OR VERTICAL |
| Connection Type | THREADED INTERNAL TUBE ALL ENDS |
| Style Designator | STRAIGHT THRU |
| Nominal Outside Diameter Tube Accommodated | 0.500 INCHES ALL ENDS IN |
| Operating Pressure | 3000.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 0.750 INCHES ALL ENDS IN |
| Disk Loading Method | SPRING |
| Media for Which Designed | OIL, HYDRAULIC SECOND RESPONSE |
| Media for Which Designed | AIR FIRST RESPONSE |
| Thread Class | 3B ALL ENDS |
| Material | STEEL BODY |
| Material | STEEL SEAT |
| Material | STEEL COMP 316 FLOW CONTROL DEVICE |
| Thread Series Designator | UNF ALL ENDS |
| Valve Operation Method | AUTOMATIC |
| 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 |
|---|---|
| 79010301 ASSY CS-800-S-20-V | R.h. Industries, Inc. (USA) |
| CS-800-S-20-V PRIMARY | Parker-Hannifin Corporation Dba Pneutronics Div Hydraulic Valve Division (USA) |
| Reference | Meaning |
|---|---|
| 79010301 | D/9 Drawing number reference only R.h. Industries, Inc. |
NSN 4820-01-407-2965 is a Valve,check, manufactured by Parker-Hannifin Corporation Dba Pneutronics Div Hydraulic Valve Division, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-407-2965 has 2 manufacturer part numbers on file: 79010301 ASSY CS-800-S-20-V (R.h. Industries, Inc.), CS-800-S-20-V (Parker-Hannifin Corporation Dba Pneutronics Div Hydraulic Valve Division).
Key specifications for CS-800-S-20-V: Flow Control Device: POPPET; Connection Style: FLARE (TUBE) ALL ENDS; Mounting Position: HORIZONTAL OR VERTICAL; Connection Type: THREADED INTERNAL TUBE ALL ENDS. 18 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.