Caryaire Double Louver Grills features 2 sets of fully adjustable blades to provide maximum flexibility in supplying air into an occupied space. The Front Louvers can be Horizontal (Model DL101) or Vertical (Model DL102). The Rear louvers have opposite orientation as compared to the front. They are usually used to supply air from the side wall . The attractive beveled edge frame has a standard width of 18mm and can be supplied in the optional 23mm width as well.