The Cover,outlet Valve, cataloged under National Stock Number 4240-01-221-0392, is classified within Federal Supply Class 4240 (Safety and Rescue Equipment) of the Fire Fighting, Rescue, and Safety Equipment group. Government technical data includes 1 specification, cited from the U.S. Government catalog. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 2 items share a part number with this NSN in the catalog (possible match — not a government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 | 4240-01-221-0392 |
| Item Name | Cover,outlet Valve |
| FSC / FSG | 4240 / 42 — Safety and Rescue Equipment |
| Status | ACTIVE |
| General Characteristics Item Description | O/A DIA 2.312 INS; 2.730 INS LG; C/O VALVE COVER PN 0083-25878; FLOW CONTROL OUTLET PN 0083-27121-02; HOUSINGVOICEMITTER PN 0083-27120 |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | Possible hazard — SDS may be required (DLA HMIC P) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| 305801 | 5/9 Secondary reference Mine Safety Appliances Company, Llc Dba M S a |
| 5-1-1455 | 3/2 Design control — primary reference U.S. Government activity |
NSN 4240-01-221-0392 is a Cover,outlet Valve, classified under FSC 4240, Safety and Rescue Equipment. Status: active.
2 possible matches (shared part number, not a government interchangeability claim): 6750-01-427-4894, 1005-01-705-8833. Verify interchangeability with system specifications before substitution.
Key specifications for 4240-01-221-0392: General Characteristics Item Description: O/A DIA 2.312 INS; 2.730 INS LG; C/O VALVE COVER PN 0083-25878; FLOW CONTROL OUTLET PN 0083-27121-02; HOUSINGVOICEMITTER PN 0083-27120. 1 specification is 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.