One of the unusual features of this watch is the steel screw-on case back that threads into the plastic case of the watch. From a series of Casio Marlin watches released in the early 1980s that all share the same case design: W-100, W-200, W-300 and W-400. The W-400 features the same Module 106 as the first Casio Marlin watch, the H-101. Blue stripe on crystal - most common Orange stripe on crystal - rare version
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Casio Marlin Digital W-400 module 106 JAPAN made Vintage 1984
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Casio Marlin Digital W-400 module 106 JAPAN made Vintage 1984
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VINTAGE CASIO W-400 marlin alarm chrono lcd watch from 1982 japan
Casio Marlin Digital W-400 module 106 JAPAN made Vintage 1984
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