This watch embodies pure simplicity, stripping away excess to reveal the essence of timekeeping. Its ultra-thin design, just 1.00 mm thick, delivers a weightless feel on your wrist, defying both gravity and stress. The moment you put it on, you experience the joy of unity with your watch. Powered by light, the Eco-Drive One is the world’s thinnest* light-powered watch, a masterpiece that only Citizen could create. As a manufacture d’horlogerie, Citizen oversees every stage of production, from crafting individual parts to final assembly, ensuring unparalleled quality and innovation.

*As of February 2018, per Citizen research.

Nearly every component in this watch was crafted from the ground up. Consider the rotor, the heart of any timepiece. Standard rotors have a three-part structure, which couldn’t fit into a 1.00mm movement. To overcome this, we dramatically reduced its size by adopting a two-part structure and an innovative welding technique. The same groundbreaking approach was applied to the coil and power cell, redefining traditional watchmaking. By challenging conventional methods, we created something truly revolutionary, pushing the boundaries of design and engineering to achieve unparalleled thinness and performance.

Eco-Drive One redefines elegance by blending thinness and strength in its design. As a watch becomes thinner, its beauty increases, and with this model, we push the boundaries of both form and function. By using innovative materials that offer exceptional durability while maintaining an ultra-slim profile, we achieve a harmonious balance of aesthetics and performance. The result is a timepiece that not only looks stunning but also endures the demands of everyday wear. With Eco-Drive One, thinness and strength come together to create a masterpiece of modern watchmaking.

Each Eco-Drive One watch is hand-assembled by CITIZEN’s skilled master craftsmen, who utilize innovative techniques to achieve its record-setting thinness. After 85 components are meticulously prepared, they are brought to our experts for assembly. To achieve the watch’s remarkable 1.00 mm thick movement and 2.98 mm case—making it the world’s thinnest light-powered watch—we developed entirely new assembly methods. CITIZEN’s role as a manufacture d’horlogerie allows us to handle every aspect of production, from crafting individual parts to final assembly, ensuring unparalleled precision and quality in every timepiece.
 

Eco-Drive, pioneered by CITIZEN in 1976, is the core technology behind Eco-Drive One. Light passing through the dial is converted into electrical energy by a solar cell. This energy charges the power cell, which then powers the motor to drive the hands. Now capable of charging in both dim light and sunlight, Eco-Drive eliminates the need for battery replacements. The technology has also extended running time to over six months on a single full charge. Continually evolving, Eco-Drive pushes the boundaries of what’s possible, setting new standards in watch technology and sustainability.