Seiko's 6139 automatic chronograph - like this all original mid-1972 Seiko 6139-6012 for sale here, a historical movement in its own right - was one of the first automatic chronograph movements created, and rightly counts itself within the ranks of the first automatic chronographs, like Heuer's Calibre 11 and Zenith/Movado’s El Primero movements. Seiko did their homework when they designed these deep blue dials, and pictures do not do these justice - these dials are amazing to behold in person - and this dial, in flawless condition, is no different.
Back in the 1970’s, Heuer and Zenith had taken a strong foothold in the sports watch industry by racing to become the first to produce an automatic chronograph. It has been a feat debated who really won between the two, but in the background of this skirmish, Seiko quietly created one to call their own – the 6139.
The 6139 was the first chronograph to have a vertical clutch, a feature considered by many to be one of the hallmarks of a superior automatic chronograph movement. The 6139 also features an automatic column wheel timing control, vertical coupling mechanism, and is an integrated chronograph – the first in the world – which means the entire 6139 movement was designed and built to be a chronograph, vice being an automatic movement with a mere timing module added (**cough cough** the Calibre 11).
With this movement, Seiko set the standard, which was followed by the Swiss watch industries 20 years later. The same movement configuration was adopted by Rolex when it made its own in-house movement for the Daytona in 2000, 30 years after Seiko released the caliber 6139 and 6138. This particular Seiko 6139, the 601x variant, represents yet another variant of Seiko's famed 6139 automatic chronograph line.
This 6139 comes with a leather strap, NATO strap, Pelican travel case, and springbar tool.
1972 Seiko 6139-6012 Automatic Chronograph
DIAL: Original radiant Seiko-signed deep blue dial; original minute and hour hands, with original chronograph hands on main and subdial. Day/date at 3 o’clock positionm with Spanish/English day variants, works nicely. Original lume patina is nearly non-existent. and remains an excellent pearly white.
CASE: Original 39mm x 43.5mm stainless steel case in pre-loved condition - no deep scratches. Caselines aren't as sharp as they should be, and there is evidence case was machine polished at some point. Regardless, case remains attractive - and the polish doesnt overly detract from overall appearance.
CRYSTAL: Correct flawless hardlex crystal, no scratches.
BAND: Light brown leather strap, with stainless-steel hardware. This 6139 also comes with a one-piece black and beige velcro "NASA" astronaut strap, with stainless-steel hardware.
MOVEMENT: Original Seiko 17-jewel 6139B automatic movement, manufactured in April 1972.
CROWN: Recessed original unsigned stainless steel crown.
CHRONOGRAPH PUSHERS: Chronograph pushers depress with satisfying click – no stick; original chronograph main and subdial hands reset as designed to 0.