Humbert-Droz is a French watchmaking house based in Besançon, built on four generations of family expertise. Its story began after the Second World War with Marcel Humbert-Droz, a Swiss watchmaker and close collaborator of Fred Lip. In 1956, he founded his own workshop, specialising in the assembly and servicing of mechanical watches. The family subsequently developed extensive expertise in maintaining high-end timepieces for prestigious watchmaking houses. Since the 2010s, Humbert-Droz has designed its own collections, assembled in its workshop in Besançon. The brand combines French watchmaking expertise with Swiss mechanical movements, notably from La Joux-Perret. For diving, the HD9 collection translates this philosophy into a sports watch designed for underwater environments. Water-resistant to 200 metres and fitted with sapphire crystal and luminous elements, it is intended for divers, freedivers and underwater explorers. Its La Joux-Perret G100 automatic movement notably provides a 68-hour power reserve. Humbert-Droz therefore offers a distinctly French interpretation of the mechanical diving watch, combining family heritage, robustness and limited-series production.