The Chronomaster Open model leaves no-one indifferent. The open dial – a Zenith creation – lets one see into the perfectly synchronized pulsations and the magic of the mechanism in what is today unanimously considered as the “best serial movement in the world” for its performance and its chronometric reliability. Its secret lies in its number of vibrations, which is 25% higher than in other movements on the market. Whereas other timepieces make 8 vibrations per second, the El Primero caliber makes 10 in the same time. Over and above the aesthetic success of this open-heart operation – the Open concept is the realization of technical prowess: to make the regulating organ visible, it has been moved to 10 o’clock, on the edge of the movement.
The great watchmaking tradition – Everything here evokes the great tradition of watchmaking: a column-wheel chronograph mechanism; a power reserve indicator; a rhodium-plated plate, circular-graining and chamfered bridges; strokes drawn on the hammers, levers and conveyors; oscillating weight with “Côtes de Genève” guilloché work; revelation of the Zenith star through skeleton work and tachometric scale on the flanges that harks back to the chronographs used in the first automobile races. One can only admire the attention to detail.
Aesthetic daring – The Chronomaster Open displays an avant-garde design with highly finished features. This aspect is important in the choice of a watch, one of the only pieces of jewelry worn by men, an accessory that identifies and highlights his personality. Zenith communicates the image of a highly technical brand that is intended for connoisseurs of high-precision watchmaking.
Variations – Using the design codes of the past to interpret contemporary models, the Chronomaster Open is based on a century and a half of watchmaking expertise. The Open model exists in four different versions: a silver or black sun-burst dial in a steel case or silver sun-burst dial in an 18-carat rose gold case or in a rose gold and steel case. The markers and the three hands for the hours, minutes and small seconds are facetted, rhodium-plated, and hand-set. The central hand of the chronograph, the hand for the 30-minute counter and for the power reserve have a blued finish. The curve of the hands that decorate the dial is executed with precise handwork. The Chronomaster Open model belongs to Zenith’s “Iconic” family.
Movement – El Primero 4021P, Automatic. Caliber – 13 1/4 “` (Diameter: 30 mm). Height 7.85 mm. Parts 248. Jewels 39. Frequency – 36,000 V/h – (5 Hz). Power reserve – Approximately 50h.
Regulator assembly with fine adjustment. Central rotor on ball bearings. Automatic winding in both directions. Rapid date reset. Chronograph function. Chronograph control center via column wheel.
Decoration – Rhodium-plated platinum. “Côtes de Genève” or circular graining and chamfering on the bridges. Strokes drawn on the hammers, levers and conveyors.
Oscillating weight – Metal oscillating weight with guilloché work in a “Côtes de Genève” motif and revelation of the Zenith star through skeleton work.
Functions – Central hours and minutes. Small seconds at 9 o’clock. Second chronograph counter in the center. 30-minute counter at 3 o’clock. Power-reserve indicator in the center.
Case – Diameter 42 mm. Crystal – Sapphire glass treated with anti-reflection on both sides. Case back – Transparent sapphire glass.
Water resistance – 10 ATM / 100 meters.
Available models – Available in steel, 18-carat two-toned or rose gold with silver or black sun-burst dial and a brown or black alligator-skin strap.