Czapek & Cie unveils the Promenade Transparencies Aqua Blue, a new limited edition of 38 pieces built around a smoked sapphire dial that subtly exposes the in-house skeletonised Calibre SXH7 in its entirety, front and back.
Two years after the original Promenade Transparencies Viridian Green made its case for radical clarity, Czapek returns to the same idea with a different palette. The premise has not changed: a dial made of sapphire crystal rather than metal, engineered to let the eye travel directly into the movement's architecture. What changes is the chromatic register, and with it, the opportunity to revisit two technical elements of the piece, the coloration of the crystal and the treatment of the hour markers.
The Metallization of Sapphire
The dial is not lacquered, painted, or tinted through the sapphire's mass. Its blue fumé gradient is produced through metallization, a vapour-deposition process in which a metallic coating is applied to the underside of the sapphire disc in a pattern of microscopic dots roughly eight microns in diameter, each several times thinner than a human hair. The density of these dots increases toward the periphery of the dial and thins toward the small seconds register at 4:30, producing the graduated blue tone without altering the optical clarity or the mechanical transparency the collection is named after. The result is a sapphire disc that remains fully see-through at its centre and progressively opaque at its edge, a property achieved at the level of coating density rather than pigment.
Unlike the metallic hour markers of the Promenade Transparencies' first edition, the Aqua Blue introduces a new execution: each index is a block of Superluminova in light blue, luminescent in the same light blue tone after dark, applied by hand and affixed to the sapphire crystal dial.
In-House Calibre SXH7
Visible from both sides of the case, the automatic Calibre SXH7 is a fully skeletonised evolution of Czapek's Calibre SXH5, redesigned specifically to be as compelling dial-side as it is through the caseback. Its seven openworked bridges, angled from the outer edge of the movement to grip the gear train, are a direct reference to the multiple-bridge architecture of François Czapek's 19th-century pocket watches. To achieve a fully legible front, Czapek's engineers reversed the entire escapement, relocated the small seconds to a sub-dial at 4:30 so that it could be driven directly off the fourth wheel, and redesigned the crown and keyless works to sit correctly on the dial side. The micro-rotor, machined in 100% recycled platinum, is engraved on both faces.
Because the movement is fully exposed on both sides, Calibre SXH7 carries the same level of decoration and hand-finishing throughout, rather than concentrating it on the caseback alone. Open-worked ratchets, sandblasted bridges, hand-chamfered inward angles, and straight-grained flanks are applied symmetrically front and back, effectively doubling the manual finishing work required compared to a movement finished on one face only. The calibre beats at 4 Hz (28,800 vph), runs on 25 jewels, and delivers a 60-hour power reserve.
The 38mm stainless steel case, shared with the rest of the Promenade collection, is built around curved lugs and hollow flanks that keep the profile slender at 10.8mm thick. Both the dial-side crystal and the caseback are sapphire, each treated with an internal anti-reflective coating so that the movement remains visible without glare from either side. Water-resistance is rated to 50 metres.
Xavier de Roquemaurel, CEO of Czapek & Cie, comments: “Transparencies plays with the excitement of seeing some details yet not all of them, letting our imagination figure out the rest of the gearing, like the organs of a beautiful body… a sort of mechanical eroticism that has always been an inspiration behind Calibre 5 and its 'cousin,' Calibre 7. The blue shades originate from the small seconds, echoing the Promenade collection's signature off-centred small-seconds counter. A tribute to Czapek's design language, built on symmetry and surprise.”
The Czapek Promenade Transparencies Aqua Blue will be available to order exclusively through Czapek authorised retailers worldwide, the flagship boutique in Geneva, and on czapek.com as of August 20th, 2026.
