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Collections Masterpiece Collection Kodo Constant Force Tourbillon SLGT003
Kodo Constant Force Tourbillon SLGT003
Kodo Constant Force Tourbillon SLGT003
Kodo Constant Force Tourbillon SLGT003
Kodo Constant Force Tourbillon SLGT003

Kodo Constant Force Tourbillon SLGT003

Grand Seiko Masterpiece Collection
USD $350,000
Limited Edition of 20
Please Inquire About Availability

Features

Kodo - a horological milestone ten years in the making

In 2020, Grand Seiko unveiled the T0 "Constant-Force Tourbillon,” a concept movement that brings together a tourbillon and a constant-force mechanism in one unit on a single axis for the very first time in horological history. Two years later, Grand Seiko has brought the concept movement to life in a dedicated timepiece called Kodo (Japanese for heartbeat), powered by the new 9ST1 caliber.  

The SLGT003 case is constructed from both Platinum 950 (inner case) and Grand Seiko’s Brilliant Hard Titanium (outer case). With its open design, Kodo showcases the inner machinations of the impressive caliber on both sides of the case. But despite its complexity, with Kodo being a Grand Seiko timepiece, legibility and functionality remain critical. Therefore, there is a dedicated sub-dial for timekeeping, where Grand Seiko’s dauphine hands draw the eye, and the hour hand even has an extra facet at the tip to avoid confusion with the minute hand. The constant-force carriage has a ruby on one of its arms, which acts as a small seconds hand. The caliber also features a hacking function to ensure precise timekeeping. 

As the inner tourbillon carriage rotates fully once per 60 seconds, the balance vibrates at eight beats per second while the outer constant-force carriage follows its rotation at exact one-second intervals. The sounds of the active escapement and the once-per-second impulse of the constant-force mechanism harmonize to create a deeply satisfying and re-assuring heartbeat, similar to that of a musical 16th note, and it is what inspired the name.

Because there are no components between the tourbillon and constant force mechanism, there is no change to the torque transmitted from the constant-force mechanism to the balance wheel. This results in a duration of 50 hours for the constant-force mechanism, as well as a more stable balance amplitude, which improves movement accuracy. Caliber 9ST1 establishes a new standard for accuracy. Each movement is fully wound every 48 hours (as opposed to the typical 24 hours) in six positions and at three temperatures. This is twice as long as the Grand Seiko standard and other industry standards. Individual movements are tested over a period of 34 days, and the performance of each movement is recorded in an individual certificate that accompanies every watch.

SLGT003 is offered with a Himeji Kurozan calf strap, which has been called the “black diamond of natural leather.” It is treated in the same traditional way Samurai armor once was to enhance durability. To achieve its distinct sheen, the surface of the strap is painted by hand with multiple layers of Urushi lacquer. It comes fitted to a platinum three-fold clasp. SLGT003 also comes with an alternative crocodile strap with crocodile leather on both sides to maximize resistance against moisture.

Grand Seiko Kodo is a Boutique exclusive and will be available as a limited edition of 20 pieces. 

Case
Case Material : Platinum 950 and Brilliant Hard Titanium
Case Diameter : 43.8mm
Case Thickness : 12.9mm
Case Length : 50.6mm
Lug Width : 22mm
Crown : Push Crown
Strap/Bracelet : Kurozan Leather Strap and Dual-Side Crocodile Leather Strap
Crystal : Box-Shape Sapphire
Special : Limited Edition of 20
Movement
Caliber : 9ST1
Type : Mechanical
Power Source : Manual Winding
Jewels : 44
Accuracy : +5 to -3 seconds per day
Duration : 50 Hours
Functions
Features : Time, Power Reserve Indicator, Tourbillon, Constant Force
Water Resistance : 100m
Magnetic Resistance : 4,800 A/m
Grand Seiko’s Boutique Online Services
Free 2-3 Day Shipping
2-Week Returns & Exchanges
Exclusive 6-Year Warranty
Customer Support
Grand Seiko Kodo SLGT003 Constant Force Tourbillon watch against black.
Kodo SLGT003
A concept movement like no other brought to life.
Grand Seiko Kodo SLGT003 Constant Force Tourbillon dial detail.
Kodo SLGT003
Caliber 9ST1 is the world's first constant force tourbillon as one unit on a single axis.
Grand Seiko Kodo SLGT003 Constant Force Tourbillon case detail at the lugs.
Kodo SLGT003
The case is constructed from both Platinum 950 (inner case) and Grand Seiko’s Brilliant Hard Titanium (outer case).
Grand Seiko Kodo SLGT003 Constant Force Tourbillon watch against black.
Grand Seiko Kodo SLGT003 Constant Force Tourbillon dial detail.
Grand Seiko Kodo SLGT003 Constant Force Tourbillon case detail at the lugs.
Free 2-3 Day Shipping

Free shipping is 2-3 business days via Fed Ex Signature Required. Orders placed before 2 pm ET are generally processed and shipped on the same business day, and orders placed after 2 pm ship the following business day. Orders are processed Monday – Friday, and orders placed on Holidays will be processed the following business day. Next Day Service can be purchased for $50 and includes Saturday Delivery when applicable. Please see TERMS for more.

2-Week Returns and Exchanges

Products may be returned to Grand Seiko Boutique Online within 14 days of the delivery date. Option for a return and refund or exchange is possible when the watch is returned in new, unworn condition, with all original contents included in the package. Upon receiving your return, Grand Seiko will verify the condition of the watch. If there are any missing items, damage, or wear found, you may be subject to fees accordingly. Please be sure to remove any jewelry or other watches before trying on the watch to avoid damage.  Please do not size the watch if you return it as it will not be considered new. Please contact the Grand Seiko Boutique Online team HERE to initiate a return. Please see the TERMS for more.

Exclusive 6-Year Warranty

Warranty – All Grand Seiko watches come with a 5-year international warranty. Grand Seiko Boutiques and Grand Seiko Boutique Online provide an additional 1-year warranty at no additional charge for a total of 6 years coverage under the limited warranty. Please see the TERMS for more.

Customer Support

Email, Phone, and Live chat info:

Scheduled hours of operation are Mon-Fri 9am-6pm. However, Grand Seiko Boutique teams may be able to assist at other times depending on availability.

Email: boutique.online@grand-seiko.us.com 

Phone: 888-300-8463 



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While we’re updating our system, all orders placed between March 28 and April 5 will not ship until after April 5. Thank you for your patience and understanding.