A device used to prevent passage of flame through a ventilating duct while air is flowing.
NSN 5905-01-018-1941
NSN 6110-00-281-3676
NSN 5945-01-333-8722
NSN 6650-01-184-9238
NSN 6130-01-321-5296
NSN 5975-01-112-0972
NSN 5895-00-962-8920
NSN 6645-01-064-3711
NSN 5930-01-474-2871
NSN 6645-00-716-8049
NSN 6130-01-339-9873
NSN 2925-00-265-7539