The MB&F HM4 «Thunderbolt» is a landmark timepiece that stretches the boundaries of watchmaking. Its architecture, directly inspired by the fuselage of a A-10 fighter plane, is as radical as the engine within. The HM4 features a manually wound movement developed over three years. This dedicated caliber, comprising 311 components all conceived specifically for this watch, was entirely designed by MB&F in collaboration with master watchmakers Laurent Bisse and Béranger Reynard of Les Artisans Horlogers.
 
The movement’s innovative architecture employs twin mainspring barrels to power two separate gear trains, leading to the iconic twin pods: one displaying the time, the other a precise power reserve indicator. This uncompromising vision in concept, design, and execution was rightfully awarded the Concept & Design Watch prize at the Grand Prix d’Horlogerie de Genève in 2010, cementing its status as a modern and iconic feat of innovative design. Moreover, the manufacturer confirms this was an exclusive model, with only 53 units produced during its brief two-year production run from 2010 to 2012. Completed with a warranty and box, it is undoubtedly a collector’s item.