1970, IWC went on with tuningfork-movements and invested heavily on this technology -- this model in a special hardened steel-case -- and why? Because it was not yet clear for them, quartz-movements might be a cost-effective and mass produced solution -- so they kept this field-proven stream in tuningfork-watches open.

Today, everything seems so different and an obvious mistake, right? Try to get rid of the hindsight-bias: this opens up an interesting part of your horological canvas.