The Square Bell Basic Lampshade is a part of Royal Designs, Inc. Regal Basic Shade Collection. Featuring curved lines, upgrade the look of your lamp with our classic square bell lampshade. Perfect for updating or repairing an antique or cherished home lamp. Royal Designs has been in the lampshade business since 1993 with its multiple shade lines that exemplify handcrafted quality and value. Height is measured by slant height from top to bottom of the lampshades? front face. Measurements listed as (Top Diameter x Bottom Diameter x Slant Height). Please measure your existing shade--a replacement harp may be needed for a proper fit or additional adjustment if changing the height of the shade.