If it came down to owning just one watch, there’s no question that Seiko’s 6309-7040/49 is a strong contender. Still their top selling diver to date, it’s a tool watch so perfectly executed, it remains firmly seated at the top of our list. Balance, contrast, and contouring all neatly assembled into a finished product that is much greater than the sum of its parts. A bare bones beauty that proves the adage less is in fact, so much more. This very early example from April of ‘77 checks all the boxes. The matte black dial is spotless, and carries the Suwa “S” logo above the six o’clock marker. This signifies its early production, and that it was built and cased completely in Japan. The hour markers are free of degradation or discoloration, and the luminous material has developed a perfect “sand” patina. The hands have retained their bright polished finish, and the luminous material is a true color match to the marker plots. The bezel rotates smoothly in either direction with a firm “click,” and the insert shows very little wear. The case is unpolished, and it’s original finishes are still clearly visible, along with sharp corners and edges. The case back markings are clear and crisp, and it’s free from any tool marring. Both the case back and crown screw down tightly with ample threading. The 6309A is keeping near perfect time post service, and ready for many more years of reliable service. We’ve paired it with a Seiko Z-22 flat vent strap that’s nearly identical to the original GL831, and comfortable on the wrist. Completely original aside from a replacement crystal, it is a true Seiko icon, and a must have for any collector.

Genuine Seiko Z-22 Flat Vent Black Composite Rubber

Serviced 5/19/22

Diameter- 44mm

Lugs- 22mm