Revealed last spring, the H4 represents the new generation of HYT skeleton watches. With a 65-hour power reserve, it unveiled its sculptural mechanism for the very first time and opened up a new creative universe for HYT.

Using this a its basis, HYT has returned to its favourite game: creating and surprising.  Only eagle-eyed enthusiasts will have noticed an intriguing detail on the new H4 Alinghi: the presence of two push-pieces. What could they be for, on a model with hours, minutes and seconds?

The H4 Alinghi is a piece equipped with a light source. Under the rider at 6 o'clock, HYT has concealed two LEDs. Once activated, they flood the entire dial with white light. At night, the red fluid is energised by this light source, becoming perfectly visible. At the same time, the wash of light flows into every nook and cranny of the calibre, literally bringing this skeleton architecture to life.

The source of energy is purely mechanical. "Starting with a blank sheet is what we know. That's how all our models have been created", explains Vincent Perriard, CEO of HYT Watches. "But here, with the light complication, a new challenge was set: we had to start using our own existing calibre as a complete, functional basis. We basically had to add a piece to a puzzle which was already finished"

The H4 Alinghi. © HYT

The generator has been nestled between 4 and 5 o'clock. It is invisible, and activated by the push-piece located opposite on the case middle. The process is broadly that of a dynamo: converting mechanical power into light energy. It is the rotation of the push-piece at 4:30 that winds the generator. Pressure on this same push-piece then activates the two LEDs which bathe the Alinghi in a soft white light.

This illumination is possible for a maximum of five seconds, after which the mechanism must be reinitialised. No battery is needed for this process, which is fully mechanical. Three factors made it so tricky to develop: the extreme miniaturisation, the curved shape, and the fact, once again, that no development of this type had ever been achieved before.

The H4 Alinghi will be released using the same base, with a carbon case, red liquid, white light, the team's logo on the seconds disc and a strap made from sail canvas, with just 25 pieces available.