Overview

The streamlined, faster-than-sound looking HM4 ‘Thunderbolt’ stretches horological art to its very limits. Both the aviation-inspired case and the engine inside have been described as radical, even anarchistic!

The HM4 engine is the culmination of three long years of intensive development. Each of the 311 components was developed specifically for this calibre. Horizontally-configured dual mainspring barrels drive two vertical gear trains, transferring power to the twin pods indicating hours and minutes on the right, power reserve on the left. With the dials perpendicular to the wearer’s wrist, HM4 might be described as the perfect pilot’s watch.