Zenith El Primero Grande Class XXT Open 44mm 03.0520.4021/01.M520 Polished & Serviced

In the throes of the 1960s, a fierce rivalry unfolded as four prominent brands vied to unveil the world’s first self-winding chronograph wristwatch. Heuer and Breitling joined forces, garnering support from Hamilton, Buren, and Dubois-Depraz, while Zenith and Seiko embarked on solitary endeavors. By the dawn of 1969, all four contenders had birthed chronograph wristwatches with automatic winding capabilities, each achieving this milestone in a spectacular fashion. Heuer’s Caliber 11, Seiko’s 6139, and Zenith’s El Primero showcased accurate and reliable movements, laying the foundation for diverse line-ups of illustrious successors.

Enter the El Primero Grande Chronomaster XXT Open Heart chronograph – a captivating reinterpretation of its historic predecessor. The watch boasts a large, mirror-polished stainless steel case and a stepped bezel that continues its finishing. Its grey dial is adorned with applied steel Roman numeral indices and three dart hour indices where the open-heart aperture is. The latter is framed by polished accents that harmonize with the 30-minute chronograph recorder and the small seconds subdial, and it showcases the mesmerizing movement within – the self-winding El Primero caliber 4021H, with 39 jewels and a 50-hour power reserve.

Recently serviced, this beautiful and complex movement ticks with precision underneath the freshly-polished steel.

Our offering is in superb condition and comes in a full set of boxes and papers.