A device used to prevent passage of flame through a ventilating duct while air is flowing.
NSN 5895-01-017-4838
NSN 6645-01-330-4251
NSN 5855-01-611-6544
NSN 6645-00-624-5963
NSN 6150-01-541-1645
NSN 5920-01-512-2054
NSN 5925-01-506-0593
NSN 5915-01-324-3262
NSN 6240-01-444-9956
NSN 7035-01-363-4540
NSN 6650-01-651-3713
NSN 5985-00-034-1218