(under the class definition) Structure including (1) modules each having an internal through passage or (2) channel shaped modules which are placed in channel- to-channel facing relationship to form a through fluid passage parts (1) or (2) being juxtaposed to form a barrier with a continuous passage traversing the juxtaposed parts.
SEE OR SEARCH THIS CLASS, SUBCLASS:
302.1+, for a construction with a passage from its interior to the ambient and see the references under "SEARCH CLASS" in subclass 302.1 for other constructions having hollows, passages or vents.
