Lemania 2310

The Lemania 2310 is a manual-winding chronograph introduced in 1942. It measures 27mm in diameter and 6.74mm thick, making it the world's smallest chronograph at its launch. The movement features column-wheel control, a horizontal clutch, and pink gold-plated bridges, with 17 or 21 jewels depending on the version. This caliber served as the base for the Omega Cal. 321 used in the Speedmaster, as well as movements from Patek Philippe, Vacheron Constantin, and Breguet. Production has ended, though Manufacture Fleury revived the design as the FM04.