A device used to prevent passage of flame through a ventilating duct while air is flowing.
NSN 6135-01-204-8712
NSN 6685-01-274-0759
NSN 5990-00-474-5609
NSN 5965-00-946-2021
NSN 5925-01-254-2578
NSN 6240-00-183-0750
NSN 7035-01-060-9372
NSN 5985-01-338-6686
NSN 5855-01-542-4576
NSN 5975-01-633-0321
NSN 6105-01-255-2010
NSN 6240-01-471-7617