Extension
Extensions (also known as top outs, cut outs, extenders, embellishments, etc.) are elements on a board that extend beyond the normal live (or copy) area of a billboard structure. They are used to extend design elements beyond the normal boundaries of the unit or basic restraints of a bulleting or poster. The uncommon shape and extra size works well to draw even more attention to the billboard ad. For example, Coca-Cola used ad extensions to promote Coke Zero by making a drinkable billboard ad with a straw that was capable of serving soda to NCCA Final Four Basketball fans via six fountain spouts.
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