Construction Zone Happy Birthday Jointed Foil Letter Banner. This 8 foot long banner is made of shiny foil topped pressed cardboard. Happy Birthday is spelled out in silver with a big yellow dumptruck cutout in the middle. Each letter is jointed together with a grommet for easy flexible postiioning. The letters are 7 inches long. Combine with our other Construction party supplies for a complete look. One Construction Zone Happy Birthday Jointed Letter Banner is 8 feet long.