Introducing the Citizen 'Tsuki-yomi' Radio-Controlled Moon Phase, the world’s first light-powered, radio-controlled moon phase watch. Celebrating the 30th anniversary of CITIZEN's first radio-controlled watch, this model features the groundbreaking fully analogue moon phase function. The Tsuki-yomi collection—translating to “reading the moon”—showcases the new radio-controlled Eco-Drive Cal. H874 movement, delivering ±15 seconds accuracy per month. Crafted with proprietary Super Titanium™ and artfully designed moon pattern dials, it uses CITIZEN’s unique “Luna Program” to calculate and display the moon phase daily based on multi-band radio signals. The watch features a striking blue moon surface pattern on the dial, a black outer ring, and a date display at 4 o’clock. Sustainably powered by any light source, including moonlight, with Eco-Drive technology, this never needs a battery. The watch also features a striking red pattern of the moon's surface on the dial paired with a black outer ring and date display at the 4 o'clock position, the watch boasts a 43mm case. It is powered by Citizen's Luna Program formula, the watch calculates the daily moon phase from signals received by multi-band radio transmitters automatically adjusting and displaying it at six o’clock.