Cartier introduced the Extra-Flat Ballon Bleu de Cartier at SIHH2011 . The watch is available in rose gold, white gold and platinum. The rose and white gold watches display a silver guilloche dial while the platinum has a blue dial. The case is 46 mm. These watches are numbered and limited in production.

http://www.watchtime.com/2011/02/extra-flat-ballon-bleu-de-cartier/