NSN 4240-01-128-6859 · NIIN 011286859 · Part number R5051
American Optical Co · FSC 4240 — Safety and Rescue Equipment · FSG 42 — Fire Fighting, Rescue, and Safety Equipment · CAGE 02622
Government record, cited
NSN 4240-01-128-6859 — this item is cataloged by the U.S. Government under National Stock Number 4240-01-128-6859. Manufacturer of record part number: R5051.
Also searched as4240-01-128-6859 ·
4240011286859 ·
NIIN 011286859 ·
01-128-6859 ·
FSC 4240 Safety and Rescue Equipment · CAGE 02622 · R5051
General Characteristics Item Description: FOR RESPIRATOR,MEDIUM SIZE
1 manufacturer part number on file
Manufacturer of record: American Optical Co
Identification
NSN: 4240-01-128-6859
NIIN: 011286859
FSC: 4240 — Safety and Rescue Equipment
FSG: 42 — Fire Fighting, Rescue, and Safety Equipment
Primary part number: R5051
Manufacturer: American Optical Co
General Description
The Mask and Cartridge, cataloged under National Stock Number 4240-01-128-6859, 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 American Optical Co. Government technical data includes 1 specification, 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.
Technical Specifications
Parameter
Value
NSN
4240-01-128-6859
Primary Part Number
R5051
Item Name
Mask and Cartridge
FSC / FSG
4240 / 42 — Safety and Rescue Equipment
Manufacturer
American Optical Co
Status
ACTIVE
General Characteristics Item Description
FOR RESPIRATOR,MEDIUM SIZE
Lifecycle & Compliance
Acquisition Status
ACTIVE
DEMIL Code
DEMIL Q — CCL Item — Commerce Control List
Hazard
Possible hazard — SDS may be required (DLA HMIC P)
Other items in FSC 4240 — Safety and Rescue Equipment
Items in the same Federal Supply class. No interchangeability or substitution relationship is implied.
4240-00-001-1515
4240-00-001-1515 · Item name not on file
4240-00-001-2684
4240-00-001-2684 · Item name not on file
4240-00-006-0022
HOSE,EVACUATION
4240-00-007-4576
4240-00-007-4576 · Item name not on file
4240-00-007-8182
4240-00-007-8182 · Item name not on file
4240-00-007-8183
4240-00-007-8183 · Item name not on file
4240-00-007-8184
4240-00-007-8184 · Item name not on file
4240-00-007-8185
4240-00-007-8185 · Item name not on file
Frequently Asked Questions
What is NSN 4240-01-128-6859?
NSN 4240-01-128-6859 is a Mask and Cartridge, manufactured by American Optical Co, classified under FSC 4240, Safety and Rescue Equipment. Status: active.
What part numbers are listed for NSN 4240-01-128-6859?
NSN 4240-01-128-6859 has 1 manufacturer part number on file: R5051 (American Optical Co).
What are the specifications of R5051?
Key specifications for R5051: General Characteristics Item Description: FOR RESPIRATOR,MEDIUM SIZE. 1 specification is documented in the U.S. Government catalog.
Is NSN 4240-01-128-6859 hazardous material?
Possible hazard — SDS may be required (DLA HMIC P). Hazard information on this page is shown exactly as it appears in the DLA record.
What is the DEMIL code for NSN 4240-01-128-6859?
NSN 4240-01-128-6859 has DEMIL Code Q. Demilitarization may be required before disposal or transfer to non-military entities.
Sources
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.
✓ Data cited from the U.S. Government catalog; commercial cross-references from OEM and certified industry sources.