An item with an integral porous or perforated plate, or with slits on the inside of a double wall.
NSN 6150-00-113-0764
NSN 2925-00-228-8854
NSN 5930-00-963-2017
NSN 5990-00-836-2542
NSN 5950-01-114-8138
NSN 5910-00-454-0461
NSN 6105-01-418-1877
NSN 5998-01-417-6383
NSN 5930-00-732-2509
NSN 5975-00-952-9315
NSN 5910-01-013-9388
NSN 6150-00-300-0395