First batch of gold watch Blue Balloon series Ballon Bleu de Cartier Cartier Blue Balloon watch 28 mm watch, quartz movement model WGBB0007 18k gold-filled case, grooved crown, inlaid with a cabochon sapphire, silver-plated pearlescent paint Dial, Roman numerals, sword-shaped blue steel hands, sapphire crystal, alligator leather strap, 18kk pin buckle. Case size is 28.6 mm in diameter, 9.35 mm thick. Water-resistant to 3 bar (approximately 30 meters) In layman's terms, it means waterproofing for daily use.