Grand Seiko has done something remarkable at Watches and Wonders for 2026. The headline story is the launch of the new Spring Drive UFA Ushio 300 divers, and on top of that, a new smaller case size. The new divers are available in two dial variations, the blue SLGB023 and the green SLGB025.
Of course, the main attraction is the Spring Drive UFA movement, or Ultra Fine Accuracy, first seen in 2025’s release of the 37mm SLGB003. Inside was the Caliber 9RB2, which measured accuracy not by the day, or even the month, but by the year. In fact, Grand Seiko calls it the “most accurate wristwatch movement powered by a mainspring today”.
Today we sit down with Joe Kirk to discuss the two new models and what makes this such a big step for the brand.
