Discover Cartier's precision with the Rotonde de Cartier (ref. HPI00639), a refined timepiece that blends thoughtful design with reliable performance. A study in proportion and durability: crafted in platinum and measuring 47 mm in diameter, with a thickness of 16.65 mm, defined by a round silhouette. The caseback is open, and the crystal is sapphire, delivering water resistance to 3000 meters. The dial composition is deliberate and legible: a blue tone, executed in lapis lazuli, framed by roman numerals hour markers, and breguet hands. Beneath the caseback lies dependable performance: the 9440 MC caliber. Produced in limited numbers, appealing to focused collectors. Introduced in 20132016. Comfort and balance define the wearing experience, making it an easy daily companion. Subtle transitions between textures elevate the overall impression. For buyers researching specifications and real-world impressions, this reference stands out for coherent design, dependable mechanics, and lasting relevance within modern horology.