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Brand: | Credor, Seiko, Shizukuishi Watch Studio | ![]() ![]() ![]() ![]() ![]() |
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Family: | |||
Height: | |||
Jewels: | 41 | ||
Reserve: | hours | ||
Frequency: | 43,200 A/h | ||
Winding: | Automatic, Bi-Directional Automatic Winding, Central Rotor Automatic Winding | ||
Diameter: | |||
© Seiko Credor Cal. 8L88A in the Credor GBBX998 | Complications: | Hacking Seconds, Hand Winding, Power Reserve Indicator | |
Hands: | Central Hour Hand, Central Minute Hand, Central Seconds Hand, Open Heart at 10:00, Power Reserve Pointer at 3:00 |
Distinguishing Technical Characteristics | |||||||||||
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![]() Central-Rotor Automatic ![]() Clockwise Balance Cock |
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Production: 2008 – 2009 | |||||||||||
1910s | 1920s | 1930s | 1940s | 1950s | 1960s | 1970s | 1980s | 1990s | 2000s | 2010s | 2020s |
Cal. 8L88 was the fastest Hi-Beat movement ever produced by Seiko and set the stage for the modern 9S8x Hi-Beat movement family. Although it was only ever seen in a single watch model, the limited-production Credor GBBX998, and is not widely known, it was a critical development for Seiko in the 2000s. By producing a 12 Hz (43,200 A/h) movement, the company showed the quality of its engineering and metallurgy capabilities. Twoyears after the 2008 introduction of the Credor 8L88, Grand Seiko returned to Hi-Beat movements with the 10 Hz (36,000 A/h) Cal. 9S85.
Note that some sources list the date of introduction for the Credor Juri Tenga with Cal. 8L88 as 2006, but Shizukuishi Watch Studio officially lists the introduction as 2008.
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The GBBX998 was an exclusive watch with a rectangular case constructed of 18k gold and rare Japanese lacquered wood. The “Super Hi-Beat” balance was visible through the open heart dial at 10:00. On the rear, a transparent case back showed the central winding rotor and balance. A power reserve indicator pointer was positioned at 3:00.
The watch retailed for 50 million Yen (about US$600,000), making it the most expensive Seiko watch ever produced, though the dial simply said “Credor”. The back was quite wordy, however, with “Water Resistant”, “Made in Japan – Seiko”, “8L88-00A0 – 18KT” and the production number “8 10001” listed around the aperture. The rotor was inscribed “Super Hi-Beat” and the movement shows “Seiko Time Corp/Forty One Jewels/8L88A/Credor.”
Calibre | Production | Speed | Jewels | Functions | Models |
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Cal. 8L55 | 2015-present | 36,000 | 37 | Date | Prospex SLA/SBEX |
Cal. 8L88 | 2008-2009 | 43,200 | 41 | Power reserve | Credor GBBX998 |
Cal. 9S85 | 2009-present | 36,000 | 37 | Date | Grand Seiko SBGH |
Cal. 9S86 | 2014-present | 36,000 | 37 | Date, GMT | Grand Seiko SBGJ |