<P> The first G - Shock, the Casio DW - 5000C, was designed in 1983 by an engineer working for Casio named Kikuo Ibe . It was designed to have a 10 - year battery life, be water resistant to 10 bar, and survive a 10m fall onto a hard surface . 200 prototypes were tested by dropping them from rooftops or third storey windows . </P> <P> The shock resistant design has 10 layers protecting the quartz timekeeping module, including a urethane rubber bumper, the stainless steel case, the hardened mineral glass watch crystal, the stainless steel screwed down caseback, and the "floating module" where the quartz mechanism floats free in a urethane foam cradle, with the outer buttons and LCD module attached with flexible cables . It was released in April 1983, seizing the unfilled market for highly functional watches . For the next few years Casio released several new models each year . The Baby - G series was released in 1991, targeted towards women . The popularity of G - Shocks increased rapidly throughout the 1990s, and by 1998, 19 million G - Shocks had been sold worldwide and there seemed to be a peak in demand as over 200 new models were released in that year alone . </P> <P> The line of watches now includes atomic clock synchronization and solar battery . The Cockpit Series G - Shock is the official timekeeper of Nismo Racing . Many newer G - Shocks feature metal (steel or titanium) banding and analog timekeeping . </P> <P> Twice a year the basic models are updated . New limited models are introduced more frequently through the year . As with Swatch watches, G - Shocks have become collectors items . </P>

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