(under the class definition) Device wherein the closure is provided with a cut-out portion or a movably mounted section, openable to a size to permit a person to thrust his arm through the opening to give a signal, e.g., to a following vehicle.
SEE OR SEARCH THIS CLASS, SUBCLASS:
146, for a closure adjustable as an entity while in the raised closed position to provide a vertical ventilating opening.
169+, for a closure with an independently movable wicket, and especially subclass 171 for a closure for a peep hole or letter slot.
