A device used to prevent passage of flame through a ventilating duct while air is flowing.
NSN 6110-00-568-9754
NSN 6320-01-046-5228
NSN 5910-00-395-9312
NSN 6240-01-461-0296
NSN 6105-01-495-1492
NSN 5920-01-035-2503
NSN 5935-00-233-1453
NSN 5975-01-160-8239
NSN 6105-01-416-2358
NSN 5935-01-112-0337
NSN 6650-01-040-9637
NSN 6105-01-585-1144