Up for sale is an ultra rare and highly desirable vintage Casio Cosmo Phase DW-3400 men’s digital astronomy sports watch, powered by Module 830 and produced for the Japan Domestic Market (JDM) during the 1980s. This is one of the rarest configurations of the highly collectible Cosmo Phase series, featuring the rugged stainless steel case design and Casio’s legendary astronomy display.

The watch is in full working condition, and all features and functions are operating properly. The iconic astronomy/cosmic phase display functions as intended, covering the years 1901 through 2200.

All parts of the watch are original aside from the strap, which has been replaced with a brand new aftermarket genuine Casio strap as shown in the photos.

The watch is in fair physical condition with visible signs of use and age, including wear around the bezel area where the original bezel writing is no longer present. The photos best describe its physical condition and should be reviewed carefully by interested buyers.

Key Details:

* Brand: Casio

* Model: Cosmo Phase DW-3400

* Module: 830

* Era: 1980s

* Market: Japan Domestic Market (JDM)

* Features: Astronomy/cosmic phase display (1901-2200), calendar, digital timekeeping, alarm, stopwatch

* Case Material: Stainless steel

* Strap: Brand new aftermarket genuine Casio strap

* Condition: Full working condition with visible signs of use and age

An exceptionally rare and highly collectible Casio digital model, recognized for its legendary Module 830 astronomy display, rugged case construction, and status as one of the most desirable Cosmo Phase models ever produced.

Ships carefully. Feel free to message me with any questions.