Cartier, Tank, Model: W5310007, automatic mechanical, 18k rose gold, stainless steel, case diameter: 39.2x29.8 mm The iconic square cushion-shaped case has a diameter of 39.2×29.8mm and a thickness of approximately 9.5mm. The lines are smooth and gentle, giving it a more modern feel than traditional tanks. The case and strap are made of stainless steel and 18K rose gold interlaced gold, paired with a nine-sided crown (set with synthetic spinel), which is a highly recognizable design in the Tank series. The silver-white radial dial is paired with Roman numeral hour markers and blue steel hands. There is a date window at the 3 o 'clock position. The style is elegant and versatile, suitable for both formal and casual occasions.