Grand Seiko Kodo Constant-Force Tourbillon SLGT001 Unique Piece

Grand Seiko presents the Kodo Constant-Force Tourbillon SLGT001, a unique piece which will be auctioned in December as part of The New York Watch Auction: SEVEN at Phillips Watches.

Grand Seiko Kodo Constant-Force Tourbillon SLGT001 Unique Piece

Early this year, the Japanese premium watchmaking brand reached a new milestone with the introduction of the Grand Seiko Kodo Constant-force Tourbillon.

Its uniquely innovative movement combines a tourbillon and a constant-force mechanism as one unit on a single axis for the very first time in horological history.

Kodo is the Japanese word for heartbeat. With its unique appearance when in motion and with its carefully designed sound, this revolutionary watch reveals its vitality both audibly and visually, thanks to the open-work design and the sapphire case back.

In 2020, Grand Seiko introduced the “T0 Constant-force Tourbillon”, a concept movement incorporating a constant-force mechanism and a tourbillon as one unit on a single axis.

To bring the concept to life in a finished watch required the complete dedication of a team comprising designers, engineers, and craftsmen and women entrusted with the assembly and finishing of the movement and the case.

Each of the 340 components of the caliber was re-examined and, where necessary, re-designed and re-engineered for production. The result is Caliber 9ST1. Not only is Caliber 9ST1 smaller than its concept movement predecessor, but its high accuracy remains stable for longer thanks to the constant-force mechanism.

Furthermore, Caliber 9ST1 sets a new standard of accuracy, verified in a testing procedure during which each movement is tested for a full 48 hours in each of six positions and at three temperatures. This is twice as long as the Grand Seiko Standard.

Each movement is assessed over 34 days to verify its accuracy. When the tests are completed and this new standard has been met or exceeded, the performance characteristics of each movement are defined in the individual certificate provided with every watch.

For the Kodo model unique piece to be sold exclusively by Phillips Auction, SLGT001, the concept was based on musō 無双. Musō roughly translates to “one and only” or “second to none,” a fitting term for the unique piece exclusive to the auction.

Grand Seiko Kodo Constant-Force Tourbillon SLGT001 Unique Piece

This unparalleled model is unique in several ways compared to the global model limited to 20 pieces, reference SLGT003.

First, the multi-component case structure is made entirely of Grand Seiko’s proprietary alloy, Brilliant Hard Titanium. This material, which is used on only the outer case and outer construction of the bezel of SLGT003, is used for both the inner and exterior case components to thoroughly reduce weight and achieve a comfortable feel unique to this model.

Brilliant Hard Titanium is as light as pure titanium but twice as hard as stainless steel and, therefore, highly resistant to scratches. Its color is brighter than the other forms of titanium used for Grand Seiko, allowing the Zaratsu polished surfaces to stand out more prominently.

The bridges, mainplate, and many of the components of the movement are plated in a silver color to create an entirely new aesthetic for the Kodo. A yellow-gold accent for the power reserve and seconds track of the carriage inherits the aesthetic of the T0 concept movement.

The design of the screws for the Kodo model has the appearance of the six arms of the carriages, a trait that cleverly enhances the design but also is pleasant for assembly.

The special screwdriver and screws used have an even application of torque, which the designer of T0 and Kodo, Mr. Takuma Kawauchiya, enjoys greatly. For the unique piece SLGT001, the screws are tempered blue by hand instead of being mirror polished as they are on reference SLGT003.

The carriages for the constant-force tourbillon mechanism are titanium to help reduce weight and improve efficiency. They are blue as well, which is executed through anodic oxidation.

The GS letters are specially engraved by hand on the Brilliant Hard Titanium clasp by Grand Seiko’s very best engravers. The watch comes with a calf strap specially treated in the same traditional way as was used to create the high-durability material once used in the armor of the Samurai.

Grand Seiko Kodo Constant-Force Tourbillon SLGT001 Unique Piece

The strap’s surface is painted by hand with Urushi lacquer in a multi-coating process that gives the strap a delicate sheen. It is in a brown color specially for this unique piece.

The Grand Seiko Kodo Constant-Force Tourbillon SLGT001 Unique Piece will be auctioned in the upcoming Phillips The New York Watch Auction: SEVEN on December 10-11, 2022 in New York City.

For the future owner of the unique piece Kodo SLGT001, the brand is offering an exclusive trip to Japan to meet its creators at the Grand Seiko Studio Shizukuishi.

A portion of the sale of this unique timepiece will be donated to the Children’s Heart Foundation, a leading organization dedicated to funding congenital heart defect research.

Technical details

Model: Grand Seiko Kodo Constant-force Tourbillon, reference SLGT001

Caliber 9ST1
Driving system: manual-winding
Vibrations: 28,800 vibrations per hour (8 beats per second)
Accuracy: +5 to -3 seconds per day (when static for 48 hours)
Power reserve: 72 hours
Number of jewels: 44
Constant-force Tourbillon (Constant-force: 50 Hours)
Diameter: 35.0mm, Thickness: 7.98mm

Other Specifications
Brilliant Hard Titanium case
Box shaped sapphire crystal with anti-reflective coating
See-through case back
Water resistance: 10 bar
Magnetic resistance: 4,800 A/m
Diameter: 43.8mm, Thickness: 12.9mm
Calf strap with Platinum 950 three-fold clasp with push button release
Double-sided crocodile strap included

Unique Piece 1/1