Oeneo is a group quoted on the stock exchange that produces cork stoppers branded Diam Bouchage. Cork is purified through Diamant patented process, which guarantees sensorial neutrality and respect of the flavors and assures differentiated homogeneity and permeability. Caps are made individually and vary in size according to the shapes of the wine bottles. They are guaranteed singly without cork taint (TCA releasable under 0.5 ng/l limit of quantification), and the eradication of undesirable molecules assures the absence of sensory deviations. They provide better performance in keeping CO₂, for perfect effervescence. The range includes caps with different permeability levels and ageing duration. The following advantages stand out: perfect mechanical memory, to spring back quickly; lack of technical defects such as dry veins, cork hardening, washers’ split and detachment; regular return of the mushroom cork; step facilitated during compression phase; lack of sensorial deviation.