Extends 21 In. to 35 In. This measurement does not include the Silhouette is or finial ends. Silhouette is 4 1/2 In. W x 3 1/4 In. H. BACKETS ARE INCLUDED and Measure 3/4 In. Width x 1 1/4 In. High x 2 5/8 In. Depth.When mounting the bracket on the side of the 3/8" rod  it should be placed 1/16" higher than the other side.