YEMA CMM-20

The CMM-20 is an automatic micro-rotor caliber introduced by Yema in 2024. Operating at 28,800 vph with a 70-hour power reserve, it features sweep seconds and Incabloc shock protection, and can be handwound via the crown. The movement was developed by independent engineer Oliver Mory through OM Mechanics, with Yema manufacturing the bridges and mainplate in-house at its Morteau, France workshop—technically a manufacture caliber rather than fully in-house. It powers the Superman Slim and other current Yema models.