ZENITH CHRONOMASTER Sport Skeleton 2026: High-Frequency Precision Meets Openworked Design

A bold new skeletonized chronograph unveiled at Watches and Wonders 2026

The ZENITH CHRONOMASTER Sport Skeleton, unveiled at Watches and Wonders 2026, represents a striking evolution of one of the most iconic high-frequency chronographs in modern watchmaking. By combining the legendary El Primero movement with a fully openworked architecture, ZENITH reveals the mechanical complexity behind its most emblematic calibre while introducing a new level of ergonomic innovation.

The Legacy of the El Primero Chronograph

Since its introduction in 1969, the El Primero has stood as a benchmark in horology, widely recognized as the world’s first automatic, integrated high-frequency chronograph. Operating at 5Hz, or 36,000 vibrations per hour, it set a new standard for precision and performance in mechanical watchmaking.

Today, the CHRONOMASTER Sport Skeleton continues this legacy with the El Primero 3600 calibre, capable of measuring 1/10th of a second. Unlike conventional chronographs, where the central seconds hand completes one rotation per minute, this movement drives a hand that completes a full rotation every 10 seconds. Each increment corresponds precisely to one tenth of a second, read directly on the 10-second graduated ceramic bezel. This unique feature makes high-frequency precision not only functional but also visually engaging.

A Transparent Architecture of Performance

With the CHRONOMASTER Sport Skeleton, ZENITH brings the movement to the forefront through a sophisticated openworked design. The sapphire dial, subtly transitioning from a smoked black gradient to full transparency, reveals the intricate structure of the El Primero 3600SK beneath.

Despite the skeletonization, the movement retains its structural integrity and chronometric performance. The iconic tri-colour overlapping counters in grey, anthracite, and blue remain a signature element, directly referencing the original El Primero from 1969. Baton-style applied markers and faceted hands coated with Super-LumiNova ensure optimal legibility, maintaining the balance between aesthetics and functionality.

Advanced Movement Engineering and Performance

Visible through both the dial and sapphire caseback, the El Primero 3600SK showcases key technical elements such as the blue column wheel and horizontal clutch architecture. The movement also incorporates a silicon escape wheel, enhancing both precision and durability.

Operating at 36,000 vibrations per hour, the calibre delivers a power reserve of up to 60 hours, demonstrating that high-frequency performance does not compromise autonomy. A stop-seconds mechanism allows for precise time-setting, while the openworked rotor, engraved with the ZENITH star, maximizes transparency without sacrificing winding efficiency.

Sporty Design with Refined Details

The CHRONOMASTER Sport Skeleton is housed in a 41mm case featuring alternating brushed and polished finishes, reinforcing its sporty yet refined character. The classic pump-style pushers preserve the watch’s chronograph heritage, while the scratch-resistant ceramic bezel, graduated over 10 seconds, ensures precise readability of the 1/10th of a second indication.

With water resistance up to 10 ATM, the watch combines everyday durability with high-end finishing, making it a versatile luxury sports chronograph

Four Distinct Versions and a Limited Edition

ZENITH introduces the CHRONOMASTER Sport Skeleton in four distinct variations. Two stainless steel models are available, one with a black ceramic bezel paired with the signature tri-colour counters, and another featuring a green ceramic bezel with grey-toned counters. Both versions are delivered on a stainless steel bracelet and include an additional rubber strap.

A third version is crafted in 18-carat rose gold with a black ceramic bezel, paired with a black rubber strap for a more luxurious and contemporary aesthetic.

Completing the lineup is an exclusive limited edition of just 10 pieces in rose gold, featuring a bracelet in matching gold and a bezel set with 52 baguette-cut diamonds, offering a highly exclusive interpretation of the skeletonized chronograph.

ZENCLASP™: A New Patented Folding Clasp

Alongside the new models, ZENITH introduces the ZENCLASP™, a patented folding clasp designed to enhance comfort, security, and ease of use. Developed over three years and 1,800 hours of engineering, the clasp integrates a micro-adjustment system that allows precise resizing directly on the wrist without tools.

Its ergonomic design ensures a natural fit, while the safety-lock mechanism and ceramic ball components guarantee durability and precise operation over time. Tested to withstand more than 600,000 opening and closing cycles, the ZENCLASP™ represents a significant advancement in bracelet engineering and user experience.

Technical Specifications

A New Chapter in High-Frequency Chronographs

The ZENITH CHRONOMASTER Sport Skeleton stands as a bold reinterpretation of one of the most important chronograph movements in watchmaking history. By combining high-frequency precision with a transparent, contemporary design and innovative ergonomics, ZENITH continues to push the boundaries of mechanical performance.

This latest release not only reinforces the enduring legacy of the El Primero but also positions the CHRONOMASTER Sport Skeleton as one of the most technically compelling and visually striking chronographs unveiled at Watches and Wonders 2026.

For more information, please visit the official ZENITH website.

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