Meet Swatch Sistem 51 (ref. SUTW400), a refined timepiece that blends thoughtful design with reliable performance. A study in proportion and durability: crafted in plastic and measuring 42 mm in diameter, with a thickness of 13.8 mm, defined by a round silhouette. The caseback is open, and the crystal is plexi, delivering water resistance to 3000 meters. The dial composition is deliberate and legible: a white tone, framed by none hour markers, and stick hands. Beneath the caseback lies dependable performance: the Sistem51 caliber. First released in 2013. Comfort and balance define the wearing experience, making it an easy daily companion. Subtle transitions between textures elevate the overall impression. For buyers researching specifications and real-world impressions, this reference stands out for coherent design, dependable mechanics, and lasting relevance within modern horology.