When breakthrough technology and spectacular design meet, the Citizen Tsuki-yomi A-T is reading the moon. It's the world's first moonphase watch combined with atomic timekeeping innovation from Citizen, and this 30th Anniversary model is nothing short of impressive. The styling embodies the moon's surface and a window at 6 o'clock displays the current moon phase. The timepiece measures 43mm in atone Super Titanium(tm) case, where sharp faceted edges pair with an elevated design throughout for an eye-catching aesthetic on the wrist. The blue dial works in tandem with black accents andtone touches for a display that's as handsome as it is legible. In addition to its running time, the watch features a moon phase display, world time in 24 time zones, a perpetual calendar, and day-date functionality. Powered by Citizen's proprietary Eco-Drive technology to provide light-powered vitality without ever needing a battery. Water resistant up to 100 meters. Caliber H874. 43mm Super Titanium Case Blue Dial Sapphire Crystal Moonphase World Time in 24 Time Zones Radio Control Perpetual Calendar Day-Date Super Titanium Bracelet with Fold Over Clasp with Push Buttons WR100/10Bar/333ft [Swimming, Showering & Snorkeling] Eco-Drive: Powered by any light source, continuously and sustainably, eliminating the need to replace watch batteries Citizen Style #: BY1010-57L.