Birthday Watch August 1985! Seiko 7431-5120 JDM Quartz Watch (OH)

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

Make: Seiko
Type: Analog Quartz
Model: 7431-8110
Year of Production: February 1985
Movement: 7431
Hand and Dial: Black Dial 12H Index with Plongeur Hands
Width: 26.3m
Lug to Lug Height: 32.5mm
Thickness: 6mm
Lug Width: 18mm
Bracelet: Brand-New Genuine Black Leather Strap with Silver Buckle
Pouch / Box: Brand-New EVA Type Zipper Pouch

Introduced in December 1969, the Seiko Quartz Astron is often credited as the world's first commercially available quartz wristwatch. Quartz watches use a quartz crystal oscillator to keep time, which is much more accurate than the traditional mechanical movements used in wristwatches at the time.

The quartz movement in the Astron was incredibly precise, with an accuracy of within 5 seconds per month, far superior to mechanical watches of the era.

The introduction of the Seiko Quartz Astron had a profound impact on the watch industry. It marked the beginning of the Quartz Revolution that led to the decline of traditional mechanical watches in the market and the rise of more accurate and affordable quartz timepieces.

Seiko's Quartz Astron was showcased at the Baselworld watch fair in Switzerland in 1970, where it received international attention and acclaim because this watch change horology history forever.

Here we have an August 1985 Seiko Tank Dress Quartz, Model 7431-5120 in stunning condition.

This timepiece was carefully stripped and underwent a good servicing, and its dial was meticulously cleaned, its electronic movement cleaned and touched up, demagnetised, and its battery replaced on 13 March 2026. It should be able to operate unhindered until the next battery replacement thereby providing the owner peace of mind. The crown has been uncorked to for battery preservation.

Its well-preserved tank case was also given a good clean-up and rub while maintaining its sharp lines and sexy curves. Most imperfections were removed without compromising the case shape. The crystal is original and was given a good rub as well and is also in excellent shape.

The crown is located at its traditional 3H position and is easily accessible.

The case width and height are approximately 26.3m (without crown) and 32.5mm respectively. The lug width is 18mm and the bracelet can accommodate wrists up to 20cm; hence, this watch is suitable for men and the modern women.

A vintage Maruman Super Engineer SS Bracelet accompanies the watch as part of the deal. It too was given an ultrasonic cleaning and polish and is now in excellent condition albeit scratches do exist.

The watch is 100% original Seiko components from this particular watch. No parts were replaced with aftermarket parts. 

This timepiece has not been water-resistant tested due to its age.

This is a Long Service Watch given to a faithful staff with the wordings "Commemorating 25 Years of Service - Petroleum Cargo Handling Co. Ltd."

The pictures provided show the watch in excellent condition 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. A nice purposeful carrying case or box 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 well taken care of for the next generation to savour such engineering beauty.

Yes, there are many other same models in the market, but almost all are not in the same quality condition and as well maintained as what you see here. Hence, it is a no-brainer that this one-of-a-kind timepiece will make an extremely beautiful birthday present for that special someone born in August 1985! 

This particular Seiko Tank Dress Quartz timepiece is rather rare and can only be found in Japan it seems. 

This fully serviced, with battery change and buffed August 1985 Seiko Tank Cocktail Dress Quartz timepiece with excellent conditioned dial is being sold at S$ 196.00 which is extremely reasonable. So, NO LOW-BALLERS AND TIME WASTERS PLEASE! Take note that low-ballers, trolls and wannabe advisors (whose "advise" is completely unwelcomed) will not be entertained, and should they persist, they will be reported and blocked! 

This is a very classy Seiko Evening Dress Cocktail Quartz timepiece in excellent condition; so, be unique and wear something that is almost impossible to source in such fine condition or purchase it for that special someone.