The Valve,check, cataloged under National Stock Number 4820-01-100-4873, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is Eaton Corporation Dba Eaton Inoac Div Eaton. Government technical data includes 21 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. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-100-4873 |
| Primary Part Number | BB91-A8B-04 |
| Item Name | Valve,check |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | Eaton Corporation Dba Eaton Inoac Div Eaton |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Furnished Items and Quantity | 2 NUT AND 2 TAILPIECE |
| Connection Style | PLAIN (TUBE) ALL ENDS |
| Mounting Position | HORIZONTAL |
| Connection Type | THREADED EXTERNAL TUBE ALL ENDS |
| Style Designator | STRAIGHT THRU |
| Material Document and Classification | AMS 5610 ASSN STD SINGLE MATERIAL RESPONSE FLOW CONTROL DEVICE |
| Material Document and Classification | AMS 5640 ASSN STD SINGLE MATERIAL RESPONSE BODY |
| Material Document and Classification | MIL-P-5516,CLASS B MIL SPEC SINGLE MATERIAL RESPONSE SEAT |
| Operating Pressure | 6000.0 POUNDS PER SQUARE INCH (PSI) MAXIMUM SINGLE RESPONSE LBS |
| Thread Direction | RIGHT-HAND ALL ENDS |
| Nominal Thread Size | 1.188 INCHES ALL ENDS IN |
| Maximum Operating Temp | 70.0 FAHRENHEIT SINGLE RESPONSE DEGF |
| Media for Which Designed | AIR SINGLE RESPONSE |
| Thread Class | 2A ALL ENDS A |
| Thread Quantity Per Inch | 12 ALL ENDS |
| Material | STEEL COMP 416SE FLOW CONTROL DEVICE |
| Material | RUBBER BUTADIENE-ACRYLONITRILE CLASS NBR SEAT |
| Material | STEEL COMP 303 BODY |
| Thread Series Designator | UN 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 |
|---|---|
| BB91-A8B-04 PRIMARY | Eaton Corporation Dba Eaton Inoac Div Eaton (USA) |
NSN 4820-01-100-4873 is a Valve,check, manufactured by Eaton Corporation Dba Eaton Inoac Div Eaton, classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-01-100-4873 has 1 manufacturer part number on file: BB91-A8B-04 (Eaton Corporation Dba Eaton Inoac Div Eaton).
Key specifications for BB91-A8B-04: Flow Control Device: POPPET; Furnished Items and Quantity: 2 NUT AND 2 TAILPIECE; Connection Style: PLAIN (TUBE) ALL ENDS; Mounting Position: HORIZONTAL. 21 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.