Seiko's 6139 automatic chronograph - a historical movement in its own right, like this all original and full serviced early 1970 Seiko 6139A-6010 proof/proof here - 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 late 1960's, Heuer and Zenith had taken hold of the entire sports watch industry by racing to become the first to produce an automatic chronograph. It has been a feat debated who won, but in the background of this skirmish, Seiko quietly created their own at the same time, beating the Swiss at their own game – the Seiko 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 stainless-steel "railroad" bracelet, nylon NATO strap, Pelican travel case, and springbar tool.
1970 Seiko 6139A-6010 "Deep Blue" Automatic Chronograph
DIAL: Original radiant Seiko proof-signed "deep blue" dial; original minute and hour hands, with original chronograph hands on main and subdial. The main chronograph sweep hand is of two-piece construciton, which early 6139's featured. Day/date at 3 o’clock position, with Spanish/English day variants, works nicely. Original dial hour indice lume remains an excellent pearly white.
CASE: Original 39mm x 43.5mm stainless steel case in pre-loved condition - no deep scratches. Caselines are sharp, with zero evidence of machine polish.
CRYSTAL: 6139-correct hardlex crystal, no scratches.
BAND: Stainless-steel "railroad" bracelet, which will fit an approx. 7.5 inch wrist; while clasp appears original Seiko, the bracelet itself does not, and bears a strong resemblance the excellent quality Uncle Seiko bracelets. It appears a former owner fitted an original 6139 clasp to an Uncle Seiko bracelet, a common practice. This 6139 also comes with a dark blue, white, and orange nylon NATO strap.
MOVEMENT: Original Seiko 17-jewel 6139A automatic movement, manufactured in February 1970. This 6139 received a full service in December 2020.
CROWN: Recessed original unsigned stainless steel crown.
CHRONOGRAPH PUSHERS: Chronograph pushers depress with satisfying click – no stick, and original chronograph main and subdial hands reset as designed to 0.