Grand Seiko SBGA437 Heritage Collection Spring Drive watchProduct Highlights Shinshu, where the Grand Seiko studio is located, was once a major silk production area. The dial of this watch, named "Thick Silver Radiant," pays homage to that manufacturing heritage. The fine radial pattern on the glossy dial, resembling lines drawn with silk, reflects a deep appreciation for its roots. This delicate pattern, achievable only with soft silver, is realized through a special technique applied to the silver plating.