The 1960s saw the rise of scuba diving as a popular sport. In response, IWC unveiled its first diver’s watch, the Aquatimer, Reference IW812 AD, at the Basel Watch Show in 1967.IWC's diving watches have an iconic diving bezel. Instead of a classic external bezel for setting the dive time, the watch features a rotating bezel under the glass that was operated using a second crown. The advantage of this design lay in the fact that the bezel was inside the watch and therefore did not impact the water-resistance of the case. To keep the heratige, they still use the same mechanism today.