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Rare Vintage Casio C-80 Men’s Digital Calculator Watch JDM 1980s Module 133
■ 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 C-80 men’s digital calculator watch, produced for the Japan Domestic Market (JDM) in the 1980s and powered by Module 133. This early Casio calculator model is one of the brand’s most iconic designs, combining practical computing functionality with classic square digital styling, presented here in a sleek all black colorway.
The watch is in full working condition, and all features and functions operate properly as intended, including timekeeping, calculator, and alarm functions. The screen has a bit of discoloration in the center; this is not screen bleed and does not affect the functionality of the watch. It is simply a visual aesthetic quirk that can develop on very old displays.
The watch is fitted on an aftermarket genuine Casio strap. All other parts of the watch are original.
The watch is in good physical condition but has signs of use and age. The photos best describe its physical condition and should be reviewed carefully prior to purchase.
Key Details
• Brand: Casio
• Model: C-80
• Module: 133
• Era: 1980s
• Market: Japan Domestic Market (JDM)
• Movement: Digital Quartz
• Functions: Calculator, Time, Alarm
• Case Material: Resin (all black colorway)
• Strap: Aftermarket genuine Casio strap
• Condition: Fully working; good physical condition with signs of use and age; minor screen discoloration (cosmetic only)
A standout and highly collectible Casio calculator watch, ideal for collectors of rare JDM Casio digitals and early calculator models.
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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