The Casio W-700 was a mid tier 100m water resistant watch introduced in 1984. In 1985 "C" and "SC" variants were introduced with the addition of a strap mounted compass. The original strap has "100m" embossed into the rubber. For more details on the functions of this watch please see Casio Module 548 W-700-1 - Black screen W-700-2 - Dark blue screen with red stripes W-700C-1A - Black screen, large compass on strap W-700C-1A - Red stripes on screen, large compass on strap W-700SC-1 - Black screen
Casio W-700, DigitalWatch Wiki
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Casio W-700, DigitalWatch Wiki
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Casio Module 548, DigitalWatch Wiki