The Spiegelau Siena Decanter features a generous 33-ounce full capacity in a unique, curvaceous silhouette, designed to create a cyclonic flow as the wine swirls down the vessel during the pour. Made in Germany of lead-free crystal, this decanter provides an attractive wine serving vessel at the table, as it functions to double-aerate the wine, exposing it to more oxygen and surface area with each pour, allowing the wine to develop to its maximum potential.