Zenith Chronomaster Open Heart

About This Watch

The Zenith Chronomaster Open Heart adds an additional visual dimension to the classic El Primero chronograph by revealing the escapement through a generous aperture at the heart of the dial. This opening exposes the balance wheel oscillating at the signature 36,000 vibrations per hour, providing a mesmerizing window into the mechanical soul of the watch. The El Primero 3604 caliber is a variant specifically designed for this display, with a decorated bridge visible through the aperture. At 39.5mm, the Open Heart occupies a sweet spot between the 38mm Original and the 41mm Sport, offering a refined case size that works equally well with dress shirts and casual wear. The silver-blue dial provides an elegant backdrop for the tri-color subdials and the open heart complication, while applied indices and faceted hands ensure excellent legibility. The 60-hour power reserve and COSC certification deliver the precision expected from a high-frequency El Primero movement. The exhibition caseback offers a second view of the movement, revealing the decorated column wheel chronograph mechanism and the star-shaped rotor that has become a symbol of Zenith craftsmanship. This is the Chronomaster for those who want to see their movement at work, on both sides of the watch.