A device used to prevent passage of flame through a ventilating duct while air is flowing.
NSN 5990-01-486-2556
NSN 6620-00-290-6505
NSN 5915-01-645-8584
NSN 5905-01-028-1408
NSN 6685-00-153-3914
NSN 6130-00-216-7376
NSN 6130-01-649-3535
NSN 5965-01-260-0780
NSN 7035-01-438-2108
NSN 6685-01-504-5513
NSN 5920-01-318-6054
NSN 5925-01-424-6744