The Seiko 6139 automatic chronograph – a historical movement in its own right, like the just full serviced 1972 Seiko 6139-7039 "Mini Jumbo" (so named for its strong resemblance to its bigger 6138 cousin) variant here – was one of the first automatic chronographs created and ranks with Zenith’s El Primero and Heuer’s Calibre 11. Back in the 1970’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 one theirs at the same time – the 6139.
Fast forward to late 2018, and Seiko enthusiasts were treated to the discovery that the early 1970s famous F1 racing bad boy Francois Cevert wore one while racing, hence the moniker "Cevert," which caught on in collector circles quickly.
We all know Omega was the first watch on the moon, mostly because Omega won’t let us forget (ever). However, the first automatic chronograph in space was the more humble and less publicized Seiko 6139-6005, named after US astronaut Colonel William Pogue, who wore his on the 1973 Skylab 4 mission-despite not obtaining NASA authorization–to time shuttle engine burns due to his familiarity with the watch and trust in its capabilities…trusting the lives of himself and fellow astronauts to the reliability of his 6139!
The 6139 was the first chronograph to have a vertical clutch, a feature considered to be one of the hallmarks of a superior automatic chronograph movement. The 6139 features an automatic column wheel timing control and an integrated chronograph, which means the entire movement was designed and built to be a chronograph, vice being an automatic movement with a mere timing module. The 6139 movement features a single register chronograph allowing time to be measured in increments of 30 minutes.
This Mini Jumbo comes with its original stainless-steel bracelet, NATO strap, Pelican travel case, and springbar tool.
1972 Seiko 6139-7039 "Mini Jumbo" Automatic Chronograph
DIAL: Brilliant original black dial, with quite pleasing lume patina. Original hour, minute, and red chronograph hands. Day/date - with Spanish/English day variants - at 3 o’clock position works nicely.
CASE: Original 39mm x 42.5mm stainless steel case, with good caselines.
CRYSTAL: NOS Seiko 6139-correct Hardlex crystal, no scratches, blemishes, or imperfections.
BAND: The 6139 comes with its original stainless-steel bracelet - links remain mostly tight. This 6139 also comes with a dark blue and gray nylon NATO strap, also with stainless steel hardware.
MOVEMENT: Original Seiko 6139B automatic movement, manufactured in May 1972. This movement received a full service in late March 2020.
CROWN: Recessed original unsigned stainless steel crown.
CHRONOGRAPH PUSHERS: Chronograph pushers depress with satisfying click – no sticking - and reset to zero.