Citizen Revives the Eco-Drive One: The 3.88mm Solar Watch Returns as a Limited Edition
Way back in 2016, when the Citizen Eco-Drive One was first introduced, Gear Patrol placed it among the best watches of the whole year. The original was a genuine technical marvel — a solar-powered watch thin enough to make most dress pieces look chunky. Now, for 2026, Citizen has revived and refreshed the concept in a limited-edition run: the Eco-Drive One AR5065-54W. And while it is not quite as thin as the original, it remains one of the thinnest solar watches ever made.
The number that defines this watch is 3.88 millimeters. That is the thickness of the case, crafted from black-finished, brushed stainless steel including its integrated bracelet. For reference, most watches sit between 10 and 14mm thick, so this is a remarkable achievement — and it is achieved without compromises that would wreck the wearing experience. Although minimalist in its design, the watch functions and wears just like any other time-only watch: it has hour and minute hands, simple but discernible markings, and a dressy overall style. It even retains a classic crown for adjustments, albeit a small one.
The thinness comes down to one crucial factor: the slenderness of the internal movement. Housed inside the incredibly thin case is Citizen's 8826 Eco-Drive movement, which measures just 1.0mm thick. The Eco-Drive name means what it always has — this is a solar-powered watch, built on a quartz system and powered by any light source. It never requires a battery replacement; when the reserve runs low, a little light gets it going again. For an EDC-minded buyer, that is one less maintenance item to think about for the life of the watch.
Durability expectations should be calibrated correctly. Citizen rates the AR5065-54W for 50 meters of water resistance, so it is not a dive watch — but you should not worry about it getting splashed in the rain or washed at the sink. Compared with the original 2016 Eco-Drive One, which pushed the thinness envelope even further, the 2026 revival trades a fraction of that extreme thinness for a slightly more robust package — a sensible trade that makes the watch more wearable in daily life.
The verdict: the Eco-Drive One AR5065-54W is a dress watch that disappears on the wrist and never needs a battery. In a limited edition, it is the rare revival that improves on a classic formula.