Patek Philippe is hitting 175 years old and the famed watch brand’s dropping a few gems to celebrate. Their new limited edition World Time Moon features a moon phase display at the center of the dial and comes in two different versions. There’s Reference 5575 as well as a smaller ladies’ edition Reference 7175 that features diamonds around the bezel. Our friends at Hodinkee tell us that not only did that move make it an even bigger collectible, but the World Time Moon is also the first time Patek has rendered the moon so realistically, here on two superimposed metallized glass discs. Power comes from an all-new caliber 240 HU LU that was specially developed for the sole purpose of combining the world-time function with a large moon phase display. The men’s Reference 5575 features a 39.8 mm case while the women’s Reference 7175 comes in at 38 mm. There’s a little anniversary detailing, first on the solid case back which has “PATEK PHILIPPE GENEVE 175e Anniversaire 1839 – 2014” engraved. Another one you might not notice right away is the fact that Patek Philippe’s hometown of Geneva represents Central European Time, where it’s normally Paris. The Reference 5575 will be limited to just 1,300 pieces while the women’s Reference 7175 is limited to 450 pieces. Head on over to Hodinkee to see more details.