In 2003, Zenith debuted the original Chronomaster Open, which was designed to highlight its El Primero caliber in the best possible way. It was the first time in the history of watchmaking that a chronograph revealed its regulating organ and escapement through a cut-out in the dial. The same rings true for the new Chronomaster Open launched by the brand this year at Watches & Wonders, with it adopting the iconic three-tone dial which has been an unmistakable and instantly recognizable design element of the El Primero since it was introduced in 1969, then via the legendary reference A386.

Thanks to a hesalite element in the crystal that serves as a subdial, the original layout with the three differently colored counters could be maintained while showcasing the star-shaped silicon escapement wheel through a cut out section. For this reason, the brand logo displayed on the black or white background is slightly shifted to the right. As is common for the Chronomaster, there is a tachymeter scale on the flange.
The El Primero 3600 automatic movement which measures the tenth of a second is an updated version of the caliber first used in the Chronomaster Sport, with an openworked main plate for a better view of the silicon escapement wheel and anchor, which oscillate at a high frequency of 5Hz. The powerful self-winding mechanism with an open, star-shaped oscillating weight amasses 60 hours of power reserve.

The movement can be admired through a pane of ...