The Windows 7 Whopper was sold in Japan for the promotion of Microsoft's Windows 7 operating system. The hamburger contained seven stacked beef patties and measured high, weighed almost , and had more than . It was originally planned to be available for only seven days starting on 22 October 2009. Due to its success in selling 6,000 sandwiches within the first four days, Burger King decided to extend the promotion period an extra nine days, ending on 6 November. The campaign was met with unexpected popularity in Japan, sparking multiple YouTube videos and blog posts about the burger.