sentences:  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.As the signature product of the company, it is often at the center of advertising promotions, product tie-ins, and even corporate practical jokes and hoaxes such as its 1998 April Fool's Day prank where Burger King took out a full page advertisement in several national publications, such as "USA Today", promoting a new version of the sandwich called the "Left-Handed Whopper".