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Rare Vintage Casio SG-100 Men’s Solar Digital Sports Watch JDM 1980s Module 624
■ ONE OF A KIND — THIS IS THE ONLY ONE. ONCE IT SELLS, THIS PAGE BECOMES AN ARCHIVE.
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► SELLER'S DESCRIPTION
Up for sale is an extremely rare vintage Casio SG-100 men’s solar digital sports watch, produced for the Japan Domestic Market (JDM) in the 1980s. Powered by Module 624, this is one of Casio’s earliest solar-powered models, featuring a distinctive futuristic display and layout that reflects the innovation of the era.
The watch is believed to be in full working condition, with all features and functions operating normally. When the watch is not exposed to light, the display turns off; however, it does not reset and resumes keeping time correctly once re-exposed to light. It is unclear if this behavior is inherent to the design, given the early solar technology used in this model.
All parts of the watch are original. The watch is in good physical condition with signs of use and age. The photos best describe its physical condition.
Key Details:
• Brand: Casio
• Model: SG-100
• Module: 624
• Era: 1980s
• Origin: Japan Domestic Market (JDM)
• Movement: Solar digital
• Condition: Good physical condition with signs of use and age; all functions working as intended with noted solar display behavior — photos best describe its physical condition
An exceptionally hard-to-find early Casio solar model, highly collectible and ideal for enthusiasts of vintage digital watches.
Ships carefully. Feel free to message me with any questions.
► ARCHIVE FILE: CASIO — BRAND HISTORY
Casio began not with watches but with calculation. Tadao Kashio founded Kashio Seisakujo in Tokyo in 1946, and with his three brothers developed the 14-A in 1957, the world's first compact all-electric relay calculator, incorporating the business as Casio Computer Co. that same year. The move into watchmaking came in November 1974 with the Casiotron, a digital watch whose claim to fame was an automatic calendar that knew how many days each month had, a small feat of logic that announced how an electronics firm would approach timekeeping.
Read the full Casio story — and shop all Casio watches ►► RELATED TIMEPIECES DETECTED (4)
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