What is the long-tail concept? Firms focus on selling just a few blockbuster items, thus keeping their SKU count low. Firms obtain a large portion of their revenues by selling a small number of units from almost unlimited choices. Firms sell their items primarily in brick-and-mortar retail stores that allow them to display items for a long time. Firms make approximately 80% of their sales from a few items in the short head of the distribution curb