Seiko Astron GPS Solar Limited Edition. With the strong, sleek lines of the Seiko Astron, the world’s first commercially available quartz watch, today’s Astron is designed for a new generation of leaders, breaking through to the future with excellence in both innovation and style. Available only in a controlled production run of 1,200, with the production serial number engraved on each caseback, this distinctive Limited Edition combines solid tailoring with the highest degree of accuracy possible in a wristwatch.