A device used to prevent passage of flame through a ventilating duct while air is flowing.
NSN 5835-01-046-9615
NSN 6145-01-334-9604
NSN 5920-01-555-6944
NSN 5935-01-382-9867
NSN 5996-01-618-7620
NSN 5910-01-252-9182
NSN 6150-00-404-6605
NSN 5915-00-058-0867
NSN 5950-01-481-5870
NSN 5895-00-946-8958
NSN 6240-01-225-2994
NSN 5905-01-204-3296