Each "frame" measures about 20" x 6.75". I at first thought from the picture on the label that the center part was meant to be filled with fabric, but on looking closer I am not so sure of that. So I looked online and found "Companies such as The Shutter Store USA and The Shuttershed often offer standard-sized panels, and many allow for some trimming for a precise fit", so I guess you could put panels, curtains or whatever you want in the frames.
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