The Seat,exhalation Valve, cataloged under National Stock Number 4240-01-250-3595, 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 Siebe North Inc North Safety Equipment Div. Government technical data includes 2 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4240-01-250-3595 |
| Primary Part Number | 77018 |
| Item Name | Seat,exhalation Valve |
| FSC / FSG | 4240 / 42 — Safety and Rescue Equipment |
| Manufacturer | Siebe North Inc North Safety Equipment Div |
| Status | ACTIVE |
| General Characteristics Item Description | SOLE SOURCE REQUIRED BY STATUTE 6.302 |
| Criticality Code Justification | TEXT |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | Possible hazard — SDS may be required (DLA HMIC P) |
| Criticality Code | Y |
| Part Number | Manufacturer |
|---|---|
| 77018 PRIMARY | Siebe North Inc North Safety Equipment Div (USA) |
| Reference | Meaning |
|---|---|
| 7600-18 | 3/9 Design control — primary reference Siebe North Inc North Safety Equipment Div |
NSN 4240-01-250-3595 is a Seat,exhalation Valve, manufactured by Siebe North Inc North Safety Equipment Div, classified under FSC 4240, Safety and Rescue Equipment. Status: active.
NSN 4240-01-250-3595 has 1 manufacturer part number on file: 77018 (Siebe North Inc North Safety Equipment Div).
1 possible match (shared part number, not a government interchangeability claim): 8105-01-648-5267. Verify interchangeability with system specifications before substitution.
Key specifications for 77018: General Characteristics Item Description: SOLE SOURCE REQUIRED BY STATUTE 6.302; Criticality Code Justification: TEXT; End Item Identification: NORTH SAFETY EQUIPMENT MODELS 7600,85100 AND 85200 SERIES AIRLINE RESPIRATORS. 2 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.