Discover MB&F's precision with the Horological Machines (ref. 91.SRL.BL), a distinctive model that balances proportion, precision, and presence. On the wrist, the case feels purposeful: measuring 47 mm in diameter, with a thickness of 23 mm, defined by a round silhouette. The caseback is open, and the crystal is sapphire, delivering water resistance to 3000 meters. Visually, the face is where character emerges: a see-through tone, framed by mixed hour markers, and dauphine hands. Mechanically, the watch prioritizes accuracy: the HM9 caliber. Released in a constrained run, appealing to focused collectors. Introduced in 2021. The silhouette offers presence without excess, lending confidence in a range of situations. Finishing showcases disciplined attention to detail across facets, edges, and surfaces. For buyers researching specifications and real-world impressions, this reference stands out for coherent design, dependable mechanics, and lasting relevance within modern horology.