The Hose Assembly,air Duct,air Breat, cataloged under National Stock Number 4240-00-770-0268, is classified within Federal Supply Class 4240 (Safety and Rescue Equipment) of the Fire Fighting, Rescue, and Safety Equipment group. The manufacturer of record is Mine Safety Appliances Company. Government technical data includes 17 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through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government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 | 4240-00-770-0268 |
| Primary Part Number | 85571 |
| Item Name | Hose Assembly,air Duct,air Breat |
| FSC / FSG | 4240 / 42 — Safety and Rescue Equipment |
| Manufacturer | Mine Safety Appliances Company |
| Status | ACTIVE |
| Measuring Method and Length | 300.000 INCHES NOMINAL OVERALL IN |
| Connection Type | COUPLING FIRST END |
| Connection Type | COUPLING SECOND END |
| Coupling Style | THREADED INTERNAL FIRST END |
| Coupling Style | THREADED EXTERNAL SECOND END |
| Cross-Sectional Shape Style | ROUND |
| Nominal Thread Size | 0.750 INCHES SECOND END IN |
| Nominal Thread Size | 0.750 INCHES FIRST END IN |
| Inside Diameter | 0.375 INCHES NOMINAL FIRST END IN |
| Surface Treatment | ZINC FIRST END COUPLING |
| Surface Treatment | ZINC SECOND END COUPLING |
| Thread Quantity Per Inch | 16 SECOND END |
| Thread Quantity Per Inch | 16 FIRST END |
| Material | COPPER ALLOY AND STEEL CORROSION RESISTING FIRST END COUPLING |
| Material | COPPER ALLOY AND STEEL CORROSION RESISTING SINGLE PLY |
| Thread Series Designator | UNF FIRST END |
| Thread Series Designator | UNF SECOND END |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | Possible hazard — SDS may be required (DLA HMIC P) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| 85571 PRIMARY | Mine Safety Appliances Company (USA) |
| Reference | Meaning |
|---|---|
| 73765-54X3PCF23 | 5/9 Secondary reference U.S. Government activity |
| D85571 | C/1 Advisory reference — outside the item-of-supply concept Zf Industrieantriebe Witten Gmbh |
| 73765-54X3RAPCF23 | 5/9 Secondary reference U.S. Government activity |
NSN 4240-00-770-0268 is a Hose Assembly,air Duct,air Breat, manufactured by Mine Safety Appliances Company, classified under FSC 4240, Safety and Rescue Equipment. Status: active.
NSN 4240-00-770-0268 has 1 manufacturer part number on file: 85571 (Mine Safety Appliances Company).
2 possible matches (shared part number, not a government interchangeability claim): 3120-01-277-2401, 3110-01-291-0000. Verify interchangeability with system specifications before substitution.
Key specifications for 85571: Measuring Method and Length: 300.000 INCHES NOMINAL OVERALL IN; Connection Type: COUPLING FIRST END; Connection Type: COUPLING SECOND END; Coupling Style: THREADED INTERNAL FIRST END. 17 specifications are documented in the U.S. Government catalog.
Possible hazard — SDS may be required (DLA HMIC P). 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.