Birthday Watch December 1964! Seiko Cal 66A Ref 661990 Sportsman Oversize 17J Gold-Filled Mechanical (OH)

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

Make: Seiko
Type: Mechanical
Model: Sportsman 661990
Year of Production: December 1964
Movement: 66A
BPH: 18,000
Number of Jewels: 17
Hand and Dial: 3D Solid-Gold Baton Indices with Dauphine Hands
Width: 35mm
Lug to Lug Height: 43mm
Thickness: 7.8mm
Lug Width: 18mm
Bracelet: Brand-New Good-Quality Genuine Leather Strap with Gold Buckle
Pouch / Box: Brand-New EVA Type Zipper Pouch

Launched in 1960, the Calibre 66A is a cousin of the Seiko 4361 and the 436 movement that made their debuts in 1960 as well. It is a mechanical movement with a power reserve is 43 to 45 hours when fully wound.

The objective was to create a sporty watch with certain dress watch features (i.e. slimmer thickness) with an oversized dial. This watch is the predecessor of the Seiko Sportsmatic range.

Unsurprisingly, mechanical hand wound watches are making a subtle but certain comeback in recent times because many from the younger generation have gone "retro" and vintage watches especially hand-wound units have become a must-have. This has not gone unnoticed by many watch companies so much so that Seiko, Orient etc. have launched "re-editions" of famous vintage designs; however, current movement models are used instead.

For Seiko Collectors and Vintage fans, this is a pre-SUWA (logo) December 1964 Seiko Sportsman Cal 66A 17J in near mint condition.

This extremely rare Seiko Sportsman is a sight to behold! It's original egg white dial is in pristine condition after a good clean-up, so too the 14K solid-gold baton indices, hands, and gold-filled case.

The timeless cylindrical shaped 20 micron gold-filled case was buffed as best as possible; however, there are some hairline scratches present. The crystal was replaced with an NOS crystal and given a good polish.

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

The movement was carefully stripped, cleaned, oiled, re-assembled and calibrated on 29 June 2025; hence it was overhauled and should be able to operate unhindered until the next servicing thereby providing the buyer peace of mind.

Equipped with the well revered 4361 movement, it has 17 Jewels that operate at 18,000 BPH. The time-grapher shows excellent readings of 0 seconds every 24 hours and amplitude of 267 with a super straight centered line! Such readings are truly exceptional even by brand new automatic watch standards whereby the accepted tolerance is -20- to +40 seconds a day! This is a testament to the quality, excellent power reserve, the meticulous care provided over the years, and the painstaking calibration conducted.

The case width and height are approx. 35mm (w/o crown) and 43mm respectively. The lug width is 18mm and the leather strap can accommodate wrists up to 21cm; hence, suitable for men and the modern women.

A brand new good-quality quality bamboo design genuine brown leather strap with gold buckle is provided to enhance the colour of the case and dial.

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 or modified parts.

Due to its age, this timepiece has not been water-resistant tested even though the seals are in place.

The pictures provided shows the watch in pristine condition (no dents, dings and major scratches), 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.

This extremely rare watch will make a beautiful birthday present for that special someone born in December 1964, and its value will appreciate over time.

This is a truly magnificent December 1964 Gold-Filled Seiko Seikosha DAINI in near-mint condition; so, be unique and wear a watch that is almost impossible to source in such stunning condition.