You are looking at a seriously underrated chronograph from Seiko’s golden age! This Seiko 6138-0020 Speed-Timer is instantly identifiable by its massive, circular, "flying saucer" stainless steel case, which gives it incredible wrist presence—a true testament to 1970s design audacity. Unlike the single-register 6139, the Caliber 6138 movement inside this watch is the true chronograph workhorse: a fully integrated automatic chronograph featuring two sub-dials for both 30 elapsed minutes and 12 elapsed hours!
This is the killer detail that sells the watch: the Caliber 6138 is technically superior to many competitors from the era because it features a Column Wheel and the revolutionary Vertical Clutch system. The Vertical Clutch allows the chronograph to run constantly, preventing gear wear when the timer is engaged, and provides the best possible user experience with a crisp, non-jumping start and stop. Furthermore, the 6138 is hand-windable (a feature the 6139 lacks!), giving the owner the satisfying tactile connection of bringing the watch to life—something a true collector values deeply.
Aesthetically, the dial is stunning: a deep, matte black accented by a unique blue and black 12-hour sub-dial at 6 o'clock, with the minute totalizer at 9. This specific "Tōkei Zara" model, with its stark, clean design, is a rare find in such honest condition. This is a robust, over-engineered piece of JDM history that delivers both the ultimate function (12-hour timing!) and an unmistakable, bold aesthetic.
