Grand Seiko 4520-8000 in steel, hibeat 1968 September

Maker: Seiko
Model: Grand Seiko 4520-8000 hibeat
Year: 1968 September
Case Material: stainless steel
Case Dimensions: 36mm, thickness 9mm
Caliber: 4520A 25jewels, hibeat movement
Service history: June 2026. Currently running at +3.1 seconds/day.
Lug Width: 18mm
Bracelet/Strap: generic grey epsom strap
Box/Papers: none
Caseback: Original GS gold medallion.

The Grand Seiko 4520-8000 is a historically important timepiece produced by Daini Seikosha Kameido factory, a subsidiary of Hattori Watch Company (aka. Seiko). One of the standout features of the Grand Seiko 4520-8000 (and its date brother 4522) is its slim "grammar of design" case profile. At just 9mm thick, this watch is much thinner than many other mechanical watches of the era. The case famously was designed by Tanaka Taro, Seiko's first in house designer, and was introduced in the 44GS - also produced by the Kameido factory. Powering the Grand Seiko 4520-8000 is the high-quality 4520A caliber-developed in-house by Daini Seikosha and arguably the greatest movement made by Seiko, ever. Introduced in 1968, the Hi-Beat caliber 45 was used in both the King Seiko and Grand Seiko models, and is loved by Seiko enthusiasts around the world for its incredible accuracy. The 45 family of caliber's consists of the 4502A, 4500A, 4520A, 4522A, and the 4580. Hi-beat (that is a movement with 36000 bph) movements existed before 1968, most notably constructed by Girard-Perregaux and Suwa Seikosha, but the caliber 45 was designed by Daini Seikosha completely from scratch and in-house. The 45 family of movements represent the pinnacle of Japanese watchmaking achievement as its derivative competed in the 1968 Geneva watch competitions where it swept the mechanical watch category for accuracy beating out top Swiss watchmakers. 

Offered here is an all-original Grand Seiko 4520-8000 presented in good vintage condition. The case has seen polishing at some point in its life, though it still retains its distinctive Tanaka-designed silhouette and strong lines. The original white eggshell dial remains generally clean, showing some light signs of age with a few faint marks visible across the dial, most noticeably around the outer edges. The hands, crown, and signed case back with its gold GS medallion are all original to the watch. The medallion itself remains intact but shows some expected wear from age and use. The crystal has been replaced with a new old stock 45GS crystal. Recently serviced by our watchmaker in June 2026, the movement is performing exceptionally well and currently running at an impressive +3.1 seconds per day, reflecting the level of precision expected from a properly maintained high-beat Grand Seiko. The watch is fitted with a premium grey Epsom strap to complete the presentation.

Ships from Japan