Abstract: An air inlet device for use in automatically providing ventilation to the interior of buildings. The device has one of more openings each of which has a moveable louver pivoted at the lower side of the opening with the louver extending upwardly so that the inlet air is directed upwardly toward the ceiling of the building. Each louver extends beyond its lower pivot point and contains means for attaching weights of different amounts to the louver depending upon the static pressure within the building thereby allowing adjustment of the air flow in accordance with the static pressure.

Abstract: A snap-together shutter in which moveable louvers are mounted within a snap-together frame to allow for the convenient assembly of the shutter with or without the use of tools. The frame is comprised of frame members that are joined using corner pieces and T-pieces. For larger shutters, interior center bars may be used in combination with the frame members to support the moveable louvers. A series of flexible pivot rods are mounted within the frame, and the louvers are mounted on the flexible pivot rods.