Pennants were a series of long narrow flags along a string to decorate and display something, usually new. They were used outside the new development of Lyon Estates in 1955. When the DeLorean time machine lifted off from behind the sign, it clipped the pennants and carried them along. The pennants played an important role in saving Marty McFly from being hit by Biff Tannen's Ford Super De Luxe Convertible, becoming a handy makeshift rescue rope.