Citizen Eco-Drive One

The Citizen Eco-Drive One is widely praised for its status as the world's thinnest light-powered watch, with sources consistently citing its remarkable 2.98mm case thickness and 1mm movement. Owners and reviewers highlight its "wow factor," good build quality, and light weight due to titanium construction, with finishing compared favorably to higher-end models. The watch features a synthetic sapphire dial and a cermet bezel for protection. Some users note the absence of a seconds hand and basic functionality due to the miniaturized movement. While one source mentions a 100-day power reserve, another states it can run for 12 months on a full charge. The price is noted as $3,500 to $5,000, considered reasonable by some for the technology. However, its high price and splash-resistant water rating are seen as drawbacks by some, and a few find its aesthetic too plain, preferring other Citizen models.