Citizen Eco-Drive One (Super Titanium)

The Eco-Drive One is Citizen's statement of how thin a watch can be made: its Calibre 8826 is the world's thinnest light-powered movement, Citizen says, at just 1.00 mm, and the whole case is 3.53 mm thick. This version is Super Titanium hardened with Citizen's Duratect Alpha, the hardest grade of the treatment, which Citizen also describes as hypoallergenic, and the guide marks it nickel-free. The case is 36.5 mm across, a size Citizen pitches at both men and women, and the whole watch weighs 48 g on its bracelet. The dial is sapphire crystal, the movement runs to plus or minus 15 seconds a month, and a full charge lasts about a year in the dark. It sells in Japan for 550,000 yen.

Written 28 September 2026 from Citizen's Eco-Drive One page.