Meet MB&F Horological Machines (ref. 42.BTSL.B), a contemporary classic shaped by careful watchmaking know-how. The exterior is thoughtfully executed: crafted in titanium and measuring 54 mm in diameter, with a thickness of 24 mm, defined by a round silhouette, protected by pvd coating. The caseback is open, and the crystal is sapphire. At a glance, the dial balances texture and clarity: a black tone, framed by arabic numerals hour markers, and proprietary hands. At its heart beats a proven engine: the HM4 caliber. Issued as a limited edition, appealing to focused collectors. Initial production year: 20132013. With considered ergonomics, it feels composed during extended wear. Brushed and polished elements play with light to emphasize crisp geometry. For buyers researching specifications and real-world impressions, this reference stands out for coherent design, dependable mechanics, and lasting relevance within modern horology.