Complete Cartier Ballon Bleu collection: 33 Balloon Steel band model: W6920071 Diameter: 33mm Material: Stainless steel Features: Mechanical • Material: Both the case and the strap are made of stainless steel, and the crown is set with synthetic sapphire cabochon (the iconic "balloon" crown). Movement: Original AUTOMATIC mechanical movement. The dial is marked with "Automatic", indicating automatic winding. It stores energy by swinging the arm during daily wear The exterior features a distinctive design The curved convex crystal: The dome-shaped curved sapphire glass is the most classic identification feature of the Blue Balloon, with a retro and full visual effect Roman numeral hour markers: Bold black Roman hour markers, paired with blue steel hands, with radial guilloire decoration at the center of the dial Off-center crown: The sapphire crown protrudes at the 3 o 'clock position, inspired by the classic hot air balloon design, which is the origin of the series name