Introducing Swatch Sistem 51 (ref. YIS405G), a distinctive model that balances proportion, precision, and presence. On the wrist, the case feels purposeful: crafted in stainless steel and measuring 42 mm in diameter, with a thickness of 13.8 mm, defined by a round silhouette, protected by pvd coating. The caseback is open, and the crystal is plexi, delivering water resistance to 3000 meters. Visually, the face is where character emerges: a black tone, framed by arabic numerals hour markers, and dauphine hands. Mechanically, the watch prioritizes accuracy: the Sistem51 caliber. Initial production year: 2016. 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.