One kind of window covering with alternating sheer and opaque stripes are room-darkening zebra blinds. The blinds provide privacy and let light into the room when the stripes are aligned properly, but they also block out light when they are not. Zebra blinds that darken a room are perfect for bedrooms, media rooms, and other areas where you want to regulate how much light enters the space. They are often composed of a polyester and PVC blend and are intended to block out a large amount of sunlight.
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