A device used to prevent passage of flame through a ventilating duct while air is flowing.
NSN 6130-00-702-0402
NSN 5915-01-446-3837
NSN 6145-01-318-0059
NSN 5895-01-602-3743
NSN 6130-00-611-2447
NSN 5950-01-540-5414
NSN 5945-01-255-3134
NSN 5985-01-566-5521
NSN 5905-01-586-3981
NSN 6620-01-329-7510
NSN 6610-01-234-5542
NSN 6320-01-564-0893