Franck Muller’s Aeternitas Mega 4 delivers a record-breaking number of complications at the time this was written.
With 36 complications, 1,483 components, a 1000-year calendar, and 5 years of research and development work — the Aeternitas Mega 4 is the world’s most complicated watch. The biggest challenge was fitting the unprecedented caliber in a space small enough to be wearable yet large enough to house three dozen complications.

The Aeternitas movement served as a base, while the Mega 4 represents the apotheosis of the art of watchmaking with its grand and small Westminster chime striking work, the only one available on the market with a tourbillon visible on the dial. Added to this are a minute repeater, a mono-pushpiece split-seconds chronograph, a perpetual calendar secular, and an equation of time that only varies by 6.8 seconds per lunar month, the equivalent of one day every thousand years!
Although the first piece of this exceptional, limited series was presented to an American collector at a ceremony in Monaco last November, the Master Watchmakers of Genthod are already putting the finishing touches to a second Aeternitas Mega 4, which will be available soon.
The price is $2.7 Million.
Photos by Franck Muller.