| 摘要 |
To enable continuous free flow of air therethrough, a base part having a first wall projecting therefrom and an opening, the opening being radially inward of the first wall, is attached to a vent cover part, the vent cover part having a second wall projecting therefrom. Each of the base part and the vent cover part are configured such that, when attached to one another, the vent cover part defines an air inlet/outlet about at least a portion of the periphery of the vent cover part, the first wall projects toward the vent cover part and the second wall projects toward the base part with a space provided between the first and second walls, and the first wall is radially outward of the second wall and radially inward of the air inlet/outlet. Together, the base part and cover part provide a ventilation passage between the interior and exterior of the building that is available at all times. |
