2018 Grand Seiko 9F GMT 25th Anniversary Green 40mm SBGN007

Here we have a 2018 Grand Seiko 9F GMT 25th Anniversary Green, reference SBGN007, limited to just 1200 pieces. Released as a highly significant milestone in the brand's heritage timeline, it was produced as a limited edition to commemorate the 25th anniversary of the legendary 9F quartz calibre, which famously marked the first time a GMT function was integrated into this pinnacle quartz movement platform. This distinctive timepiece features a 40mm stainless steel case with a curvaceous, sinuous profile that utilises Grand Seiko’s legendary hand-applied Zaratsu polishing for distortion-free mirror surfaces. The faceted case architecture features a smooth conical bezel and integrated fluid case lines, offering a versatile lug-to-lug length of 46.5mm and a sophisticated thickness of 12mm for a powerful, balanced presence on the wrist. A signed screw-lock crown. The standout feature of this model is its multi-level, deep forest green dial adorned with a stamped, repeating "GS9F" geometric monogram pattern that incorporates the historic original quartz symbol. The architectural layout features 24-hour numerals, applied polished and brushed faceted indices, and an exclusive gold 5-pointed star at 6 o'clock symbolising its enhanced high-precision regulation. Razor-sharp, polished faceted dauphine hands alongside a striking yellow arrow GMT hand are engineered for intuitive tracking. Protecting this complex design is a dual-curved sapphire crystal featuring a multi-layer interior anti-reflective coating. On the reverse, a solid screw-down caseback is beautifully decorated with the iconic Grand Seiko 18ct yellow-gold lion medallion and a custom 25th-anniversary engraving. Inside beats the proprietary Japanese-made thermocompensated Calibre Grand Seiko 9F86. This customised high-performance movement features hand-selected quartz crystals regulated to an astonishing accuracy of ±5 seconds per year, a twin-pulse control motor driving heavy hands, an anti-backlash mechanism for a precise, shudder-free tick, and an independent hour-hand adjustment for seamless global travel without stopping the watch. The watch comes paired with a 20mm bespoke three-link stainless steel bracelet that tapers into a branded twin-trigger deployant clasp.

This watch is sold with its original Grand Seiko box and paperwork. A battery change was completed with Grand Seiko in January 2026. The watch comes paired with a 20mm three-link stainless steel bracelet that tapers into a branded clasp. The watch is from October 2018 and is sold in worn condition, but overall it is in fair condition, as you can see. The watch comes with our 12-Months Warranty.

What I love most about this reference is how subtle the dial appears at first glance. Indoors, it comes across as a deep, understated green, but the moment sunlight hits it, the entire watch transforms. The colour suddenly becomes far more vibrant, and the hidden “GS9F” patterned texture starts to reveal itself properly, giving the dial an incredible amount of depth and character. It’s one of those watches that quietly flies under the radar until the lighting is just right, and then it completely comes alive. I would not hesitate to add this fantastic Grand Seiko to your collection today!

Reference : SBGN007 (9F86-0AC0)
Movement : Quartz Grand Seiko Cal. 9F86
Age : October 2018
Year : 2018
Case Size : 40mm
Case Thickness : 12mm
Lug to Lug : 46.5mm
Lugs : 20mm
Condition : Pre-Owned
Box and Papers : Box & Papers
Case Material : Stainless Steel
Warranty : 12-Months Warranty
The wrist model's wrist size is 7inch

The first Grand Seiko debuted in Tokyo in 1960 at Suwa Seikosha, established in 1942 in Nagano, Japan. Grand Seiko watches are handcrafted by highly skilled artisans and master watchmakers, often referred to as Takumi (meaning "master craftsman" or "artisan" in Japanese). In 1962, Taro Tanaka developed a set of design guidelines known as the "Grammar of Design," which aimed to create a cohesive look for Seiko watches. These guidelines encompassed nine key principles that distinguished the watches. Some of these principles involve Zaratsu polishing that makes the watch surfaces shine beautifully and reflect light in interesting ways. There’s also an emphasis on using unique shapes for the watch cases, ensuring that every part is perfectly shaped, and adding features like sharp, clean edges and well-designed hands and markers that catch the eye. Today, Tanaka's principles still apply to the modern Grand Seiko philosophy. Rather than sending its 25 Jewels Chronometer movement to the Swiss to be tested, Seiko decided to do the testing themselves. The European Chronometer Official Association believed that a chronometer-rated watch had to be independently tested to be awarded that designation. Seiko watches were not independently tested, so therefore they could not be chronometers. The ECOA did what irritated watchmakers do: they wrote a stern letter to Seiko requesting that the designation of Chronometer on Grand and King Seiko watches stop. Seiko obliged and ceased using the text chronometer on their watches. In response, the Japanese Chronometer Authorisation Association was started in 1968 as an independent group to test timepieces to chronometer standards. The Association was short-lived: due to the rise of quartz watches, it closed in 1983. Today, Grand Seiko movements are tested over 17 days in 6 positions compared to COSC testing over 15 days in 5 positions. In 1985, Suwa Seikosha became Seiko Epson Corporation. In 2017, Seiko announced that Grand Seiko would become an independent brand. Grand Seiko watches are known for their unique quality because a single craftsman puts together each one, whether it uses quartz, mechanical movement, or Spring Drive technology. In the Shinshu Watch Studio, a talented watchmaker named Yoshifusa Nakazawa leads a skilled team at the Micro Artist Studio. This special workshop is dedicated to creating some of the most intricate and beautifully designed Spring Drive watches, which are carefully finished and assembled by hand.