This tiny, privately held, Swiss company supplies Rolex with its proprietary, non-toxic, epilame surface treatment.

SuSoS's PAcrAm technology provides a convenient and highly tuneable, dip & rinse solution to finely control surface energy using monomolecular thin-films. For the purposes of mechanical timekeeping, that surface energy is tuned to keep lubricant precisely where it is supposed to be.

Based in Zurich, the firm was initially spun up as SurfaceSolutionS GmbH in 2004 (not to be confused with the Austrian firm Surface Solutions GmbH founded in 2020) and later shortened to SuSoS circa 2007. It is ostensibly associated with Rolex SA's tribological research and development division, as the company's directors, Samuele Tosatti and Stefan Zürcher, are the only names on the 2006 patent (EP1927648A1) assigned to Rolex for said surface treatment, which also happens to make extensive use of the term SuSoS to refer to the various epilame formulations that it details. This patent was later withdrawn and superseded by another, assigned to both SuSoS AG and Rolex SA, in 2011.

In their own words, SuSoS focuses on the 50 nanometers that make the difference.