The Chronoswiss Opus was introduced in 1995 as the world’s first serially produced skeletonised automatic chronograph. That founding claim has anchored the collection’s identity ever since, and the current Opus Dakar Sundown — reference CH-7522.1S-BR — is the latest iteration to test how well that original architecture translates into a contemporary finishing context.
A Two-Material Case Strategy
The most immediate design decision in the Dakar Sundown is the shift from the titanium case used in last year’s Opus Dakar to a 23-piece construction combining satin-brushed stainless steel with 18k red gold. The steel forms the main case body; the red gold is reserved for the knurled bezel, the oversized onion crown, the chronograph pushers, and the caseback ring. This allocation is deliberate: the warm metal appears at every point where the hand interacts with the watch, while the cooler, harder steel handles the structural volume.
At 41mm in diameter and 14.8mm thick, the proportions are unchanged from the established Opus template. The thickness is a direct consequence of the movement architecture — a skeletonised automatic chronograph requires vertical stacking that a manual-wind or thin-rotor construction would not — and Chronoswiss has not attempted to disguise it. The straight lugs, secured with the brand’s patented Autobloc system, keep the case geometry clean and uncluttered. A curved sapphire crystal with double-sided anti-reflective coating sits over the dial; a sapphire caseback with an 18k red gold coin-edge ring closes the case at the rear. Water resistance is rated to 30 metres.
Skeletonised Dial Architecture and Legibility
The dial of the Opus Dakar Sundown is not a dial in the conventional sense. The skeletonised structure leaves the chronograph movement almost entirely visible from the front, with the display organised around four counters: a 30-minute register at 12 o’clock, a 12-hour totaliser at 6 o’clock, running seconds at 9 o’clock, and a pointer date at 3 o’clock. A peripheral minutes and seconds track runs around the edge of the opening.
The structural elements of this skeletonised display are finished in brown CVD tones described as inspired by desert sand at dusk. CVD — chemical vapour deposition — is a coating process that allows precise colour application to metal surfaces without the thickness or fragility of paint or lacquer. Against the galvanic black bridges of the movement visible beneath, the brown CVD finish creates a layered warm-to-dark contrast that gives the watch its visual identity. The rhodium-plated Breguet-style Losange hands provide the time indication, their polished surfaces reading clearly against the complex background.
Legibility in a skeletonised chronograph is always a negotiation. The Dakar Sundown addresses this through the suspended counter registers and the contrasting hand finish, though the depth and visual complexity of an openworked layout will always demand more from the wearer than a closed dial. That is a structural characteristic of the format, not a flaw specific to this execution.
Movement Finishing: Calibre C.741S
The movement is the Chronoswiss calibre C.741S, built on an ETA Valjoux 7750 base and extensively reworked for skeletonisation. The bridges and base plate are skeletonised and finished with perlage; the bridges carry a galvanic black finish. The rotor is openworked and decorated with Côtes de Genève, and is gold-plated. The movement beats at 28,800 vibrations per hour and delivers a power reserve of approximately 46 hours.
Additional specified components include a Glucydur balance, a Nivarox I hairspring, and Incabloc shock protection. Fine regulation is handled via an excenter cam. The movement counts 25 jewels.
The decision to work from the Valjoux 7750 platform is worth noting in a design context. The 7750 is a column-wheel-free, cam-actuated automatic chronograph with a specific bridge layout that directly shapes what a skeletonised version can look like. Chronoswiss has been working with this base since the Opus collection’s founding, and the C.741S represents a mature, heavily customised interpretation of that architecture rather than a recent adaptation.
Strap and Overall Presentation
The watch is worn on a sand-coloured nubuck leather strap closed with a pin buckle. The strap choice reinforces the desert-palette theme established by the brown CVD dial structure and connects the Dakar Sundown visually to its titanium predecessor without duplicating it. Nubuck’s matte, slightly textured surface sits comfortably alongside the satin-brushed steel of the case body.
The Opus Dakar Sundown is a permanent collection reference. It represents a specific material and finishing direction for the Opus line — warmer, more formally positioned than the titanium Dakar — rather than a limited or special-edition departure. Designers and collectors interested in how a three-decade-old openworked chronograph architecture absorbs contemporary two-tone case construction and CVD colour technology will find it a useful case study.
