(under the class definition) Device provided with a passage blocking member having a plurality of openings spaced in the
same plane, and further provided with a movable closure back to back with the member and having a plurality of spaced openings therein and movable while maintaining the back to back relationship, whereby a movement of the closure aligns or misaligns the openings in the closure with the openings in the passage blocking members.
SEE OR SEARCH THIS CLASS, SUBCLASS:
95+, for a plurality of interconnected closures in spaced openings along a barrier.
SEE OR SEARCH CLASS
454, Ventilation,
196+, for a register-type ventilator combined with a window and subclasses 284+ for registers combined with heating or ventilating structure.
