The movement of this watch is a modified ETA 2893 which has been given a reference Calibre JJ03 by Christopher Ward. The modification allows the adjustments of the hour, minute, GMT as well as the reference city as indicated by the airport code in the window at the 12 o’clock position by manipulating a single crown.
Moreover, the choice of the airport code also translate to a red dot to be shown of the geographic location chosen on the C900’s 3-dimensional world map dial.
The modification made to allow a single crown to control all the complications in the watch is an achievement. In fact, I was made to understand a patent has been applied for it.
There is a display window at the case back to see the movement in action. All around the metal part of the case back, the definition of all the airport codes to the respective cities are listed.
For a traveler, this watch has a complication that makes tracking timezones a very simple affair. I like it and, if given the opportunity, I could get one.