A device used to prevent passage of flame through a ventilating duct while air is flowing.
NSN 6685-00-467-0608
NSN 6240-01-453-1591
NSN 5895-01-519-1442
NSN 5965-01-252-8701
NSN 5996-01-387-0484
NSN 6145-01-020-7722
NSN 5835-00-466-8544
NSN 5835-01-202-9673
NSN 5920-01-494-4117
NSN 6685-01-418-0925
NSN 5905-01-232-4249
NSN 7035-01-467-5564