These devices are intended to work with oxygen in wines once the wine is poured into wine glasses. Wine aeration allows the wine to be exposed to oxygen, which improves all factors of the wine and reduces tannin. Aerator pourers are normally placed at the neck of a wine bottle and these have aeration ports or holes. The wines are sucked with air in these channels to both aerate and ev... https://www.bistrotorestro.com/wine-accessories/aerating-pourers