A device used to prevent passage of flame through a ventilating duct while air is flowing.
NSN 6610-01-376-8603
NSN 5950-01-135-5438
NSN 6130-00-823-2279
NSN 6220-00-179-9104
NSN 6135-01-340-2599
NSN 5915-01-377-3545
NSN 6150-00-829-1173
NSN 6650-01-301-8806
NSN 6620-01-479-2352
NSN 5975-01-531-8232
NSN 6105-01-056-5258
NSN 6105-01-577-9186