COS operates in Terre Siciliane, the expansive wine region of southern Italy where Mediterranean heat and volcanic soils shape distinctive expressions of native grapes. The winery's portfolio centers on Sicilian varieties: Frappato, Nero d'Avola, and Zibibbo. The Cerasuolo di Vittoria Classico delle Fontane, built from Frappato, stands as the flagship—a wine that has drawn assessment from Wine Spectator, Wine Enthusiast, Wine Advocate, and Decanter. The Contrada Nero d'Avola follows closely, showcasing the dark-skinned variety's structure and depth. Zibibbo in Pithos, fermented in traditional earthenware, represents an older winemaking method applied to the white grape. Each wine reflects the terroir and varietal character of Sicily's southeastern corner, where Frappato and Nero d'Avola thrive in warm conditions, and Zibibbo—historically grown for fortified wines—finds new expression in dry form.