These extruded aluminum architectural grille that meet the Florida Building Code for hurricane wind loads on building and structures including the Rigid Missile Hurricane Impact Test. In addition, these stylish architectural louvered grilles will complement the appearance of any building or structure. Each louvered grille is made of strong, durable, extruded aluminum with a clear anodized finish to resist rust and corrosion. These louvered grilles are designed to be installed easily from inside the room to avoid long ladders or expensive aerial lifts. Louvered grille mounts securely to the back of the 42-inch x 16-inch wall sleeve and exceeds free area the 65 % minimum requirement specified by most PTAC manufacturers. Free area is the minimum area of the opening in an air inlet or outlet in which air can pass freely.