A BIRTHDAY WATCH IS A WATCH PRODUCED THE SAME MONTH AND YEAR AS YOUR BIRTH MONTH AND YEAR

Make: Seiko
Type: Automatic
Model: Sports 5 Speed-Timer Series
Year of Production: November 1974
Movement: 6139
BPH: 21,600
Number of Jewels: 21
Hand and Dial: 3D Baton Indices with Baton Hands
Width: 39.3mm
Lug to Lug Height: 42.2mm
Thickness: 15.3mm
Lug Width: 18mm
Bracelet: Original Seiko 5 Sports Signed H Link SS Bracelet
Pouch / Box: Brand-New EVA Type Zipper Pouch

A Brief History:

"Today, self-winding (or automatic) chronographs are quite common. Omega created a prototype of one back in 1948 but later abandoned their production plans. Over 20 years later, two companies and one collaboration would finally make it to series production: Seiko, Zenith, and a joint venture between Heuer, Breitling, and Hamilton. These manufacturers all introduced and launched their automatic chronograph movements in 1969, and this watch style would quickly become very popular throughout the industry.

"Of the three calibers, the Seiko 6139 has had the greatest influence on future generations despite being the least well known. This movement centers on its vertical clutch and compact automatic rotor, a design many manufacturers have imitated since the 1980s. In fact, Frederic Piguet turned to the 6139 when crafting their legendary caliber 1185, which some call the “grandfather of the modern automatic chronograph.” Considering how many automatic chronographs the 1185 has inspired, there’s no denying the 6139’s influential role.

"In 1969, Suwa Seikosha put the final touches on the caliber 6139, complete with a Magic Lever and vertical clutch system. On May 21, 1969, Seiko officially debuted the movement under the name “61 Speed-Timer.” However, the caliber had already begun appearing in watches as early as January of the same year; you can still find examples from those early months today. Seiko published the first advertisement for their new automatic chronograph in February 1969. Both the company and Ohki were unaware that the 61 Speed-Timer was the world’s first automatic chronograph movement. At the time, Seiko was busy planning the release of the quartz Astron later that same year." - The Chrono24 Magazine.

Thus, the Seiko 6139 can be considered the great-grandfather of the modern automatic chronograph timepiece!

The Seiko 6138 and 6139 movements were specifically designed for their newly developed watch range ~ the Chronograph that took the world by storm.

The 6139 is the world’s first automatic chronograph that uses a column wheel and vertical clutch. The 6138 followed shortly afterwards. Both were nicknamed “61 Sports Speed Timers” even though certain models did not indicate these wordings.

Both movements were developed in 1969 for different tasks. The 6138 was developed on the 6139 platform but with the intention of having an added chronograph hand to measure elapsed hours; and it also included the column wheel and vertical clutch for more precise stopwatch measurement. But, unlike the 6139 that only has one sub minutes dial, the 6138 comes with two ~ a 30-minute counter and a 12-hour counter.

Here we have a November 1974 Sunburst Green 6139-8040 in stunning condition.  Like most 6139s, this timepiece is only equipped with one 30 minutes mini dial that is blue with an orange second hand.

A deep cleaning was conducted on this rare November 1974 Seiko Green dial, silver day/date window, chapter ring, 3D white baton indices, baton hands and mini-dial hand as well. They are now in stupendous condition that is extremely pleasing to the eye albeit a slight emergence of patina is noticed around the small dial.

Its cylindrical shaped silver case with built-in lugs and original Seiko H Link bracelet were cleaned via ultrasonic immersion and a good polished soon followed to reveal a fantastic finish albeit a few minor scratches that comes with age.

The crystal was replaced with a Skunk Werx Customised Sapphire Jewelled Crystal and is now in mint condition.

The crown is located at the traditional 2H, 3H and 4H positions and are nicely tucked away to prevent damage or snags. The day / date and hands quickset works as it should by pushing in the 3H crown to the first and second levels to adjust accordingly. Crown 2H is for the chronograph start/stop and the 4H is for the reset of mini-dial and main second hands. All are working as they should.

Because it is a JDM, the Day is in English and Kanji, cool!

The movement was carefully stripped and meticulously cleaned via ultrasonic immersion, oiled, re-assembled, and calibrated on 11 November 2025. In short, it underwent an overhaul and not a general servicing. It should be able to operate unhindered until the next servicing thereby giving the owner peace of mind.

Equipped with the highly prized 6139 movement, it has 21 Jewels and operate at 21,600 BPH. The time-grapher shows excellent readings of -1 second and amplitude of 23 0with a consistent straight centered line! Such readings are truly exceptional even by brand new modern automatic watch standards whereby the accepted tolerance is -20 to +40 seconds a day! This is a testament to the quality, the meticulous care provided over the years, and expert calibration.

The case width and height are approximately 39.3mm (w/o crown) and 42.2mm respectively. The lug width is 18mm and the bracelet can accommodate wrists up to 17.8cm; hence, this watch is suitable for men and the modern women.

To the best of our knowledge and expertise when overhauling the timepiece, the watch is 100% original Seiko components from this particular watch. No parts were replaced with aftermarket parts.

Due to its age, this timepiece has not been water-resistant tested.

The pictures provided show the watch in stunning condition, and the movement within squeaky clean and well maintained. It has also been demagnetised to improve parts reliability, minimise wear + tear, and improve accuracy. The only drawback is the lack of documentation and original box. An aftermarket box or purposeful carrying case will be provided instead.

Bear in mind that this watch has seen many of the previous owners’ ups and downs in life and should be cherished and preserved for the next generation to savour such engineering beauty.

Yes, there are many other same / similar models in the market, but none as beautifully aged and as well maintained as what you see here. Hence, it is a no-brainer that this one-of-a-kind watch will make an extremely beautiful birthday present for that special someone born in November 1974!

This is a highly sort-after Seiko 5 Sports 6139-8040 Chronograph JDM; so, be unique and own a November 1974 Birthday Watch that is almost impossible to source in such fine condition or purchase it for that special someone instead.