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Introducing the Citizen 'Tsuki-yomi' Radio-Controlled Moon Phase - the world’s first light-powered radio-controlled moon phase movement.The watch calculates the phase of the moon each day from signals received from multi-band radio transmitters. To celebrate the 30th anniversary of the first CITIZEN radio-controlled watch we are debuting the world’s first fully analogue moon phase function for light-powered watches. The Tsuki-yomi collection (directly translating to “reading the moon”) features a new radio-controlled Eco-Drive Cal. H874 movement that provides ±15 seconds accuracy per month, revolutionary proprietary Super Titanium™ material and artfully crafted moon pattern dials. Based on a unique mathematical formula developed by CITIZEN called “Luna Program”, the watch calculates the phase of the moon each day from signals received from multi-band radio transmitters. The phase of the moon at the six o’clock position is then automatically adjusted and displayed. With a striking grey pattern of the moon’s surface on the dial paired with a black outer ring, and date display at the 4 o’clock position. Sustainably powered by any light, including moon light, with our proprietary Eco-Drive technology, this timepiece never needs a battery. Verified details include bracelet material of Super Titanium, brand collections of Atomic Timekeeping, dial colour of Silver, diameter of 43mm, guarantee of Citizen 5 Years Guarantee and movement of Eco-Drive. Available colours: Silver.