The 'Ballon Bleu de Cartier' watch gets its name for two reasons – the spherical case is reminiscent of an inflated balloon and the cabochon-topped crown appears to be floating. Making its debut back in 2006, this version is crafted from durable stainless steel and has an invisible clasp-fastening bracelet. It's detailed with black Roman numerals marking the hours on the silvered guilloché opaline dial and signature blued steel sword-shaped hands. It's a true heirloom that you can pass down through generations.