When ordering a Silhouette with Top Down/Bottom Up the continuous loop cord controls the top down and vane opening functions. Notice that there is a large bottom rail. The bottom rail controls the Bottom up function of the shade. The shading stores within the bottom rail when it is raised. One unique feature of the top down/bottom up application of Sihouette Window Shadings is the ability to open and close the vanes when the shading is only partially raised or lowered.

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