An item with an integral porous or perforated plate, or with slits on the inside of a double wall.
NSN 6620-00-355-1734
NSN 6240-01-415-3014
NSN 5915-01-513-2531
NSN 6650-01-434-6434
NSN 5935-00-196-0697
NSN 5930-01-205-2943
NSN 5990-00-166-9476
NSN 5835-01-632-6627
NSN 6130-01-237-5992
NSN 5960-01-389-0629
NSN 5855-01-316-4975
NSN 6320-01-359-3921