A device used to prevent passage of flame through a ventilating duct while air is flowing.
NSN 6150-00-227-2424
NSN 5925-01-135-7038
NSN 6220-01-605-4463
NSN 6645-01-420-8360
NSN 5905-00-959-1879
NSN 6150-00-407-7538
NSN 6610-00-966-5740
NSN 5996-00-245-6273
NSN 6650-01-315-9728
NSN 5985-01-148-1879
NSN 5960-01-196-3344
NSN 5985-00-004-6285