Czapek & Cie expands its Promenade line with the Promenade Transparencies Aqua Blue, a limited edition of 38 pieces built around a blue fumé metallized sapphire crystal dial that reveals the architecture of the in-house skeletonised Calibre SXH7 through both sides of the watch.
The sapphire dial is produced using a metallization process rather than conventional lacquer or pigment. A metallic coating is vapour-deposited onto the underside of the sapphire in microscopic dots measuring approximately eight microns in diameter.
Their density increases toward the periphery and decreases around the small-seconds register at 4:30, creating the graduated blue tone while retaining greater transparency at the centre.
For night-time legibility, applied light-blue 3D Super-LumiNova blocks serve as hour markers, glowing in a matching light-blue tone in the dark.
Visible through both sides of the watch, the automatic Calibre SXH7 is a fully skeletonised development of Calibre SXH5, introduced in 2020 on the Antartique.
Measuring 30 mm in diameter and 4.2 mm thick, the 152-component movement uses seven openworked bridges angled from the perimeter toward the gear train, recalling the multiple-bridge architecture found in François Czapek’s 19th-century pocket watches.
The movement was specifically redesigned to make its architecture equally legible from the dial side. The escapement was reversed, the small seconds were relocated to a sub-dial at 4:30, and the crown and keyless works were repositioned accordingly.
A micro-rotor made from recycled platinum winds the movement, which operates at 28,800 vibrations per hour (4 Hz), uses 25 jewels and provides a power reserve of 60 hours. Its variable-inertia balance is fitted with four gold inertia blocks.
Because the calibre is visible through both sides, its finishing extends across both faces.
Openworked ratchets, sandblasted rhodium-plated bridges, straight-grained sides and hand-chamfered inward angles are applied throughout the movement, giving the exposed architecture a consistent appearance from either direction.
The 38 mm stainless-steel case measures 10.8 mm in thickness and 42 mm from lug to lug. Its curved lugs and hollow flanks contribute to the relatively slender profile, while sapphire crystals on the front and back provide views into the movement.
Both crystals receive anti-reflective treatment on their inner surfaces, and the case is water-resistant to 50 metres / 165 feet.
The Promenade Transparencies Aqua Blue is fitted with a dark-blue nubuck leather strap, with a stainless-steel Milanese mesh bracelet also available. The watch is limited to 38 pieces and is priced at CHF 28,800 / €31,700 / US$40,300 before taxes. czapek.com
