Isotope has announced a highly limited collaboration with designer Björn Altmann, inspired by the intricate manhole covers of Osaka, Japan. The Mercury Altmann x Isotope features a dial depicting Osaka Castle surrounded by cherry blossoms and flowing water. The dial is crafted using grand feu cloisonné enamel on a sterling silver base, requiring nearly a year of work to complete the small series of five watches. Each of the five watches comes with a signed copy of Björn Altmann’s book, "Manhole Covers of the World." The production process involved hand-applied silver wires and multiple enamel layers fired at 850°C. These limited pieces are stated to be finished and ready for immediate shipping to customers. The brand also provided a technical update regarding the progress of the OVNI model. While the complex logo etching on the curved case is proceeding, a delay has been identified with the jumping hour disc. Testing revealed that temperature variations affected the aluminum disc's rigidity, leading to intermittent skipping. Isotope is currently remanufacturing these discs to improve stability, a process expected to take three to four weeks.