Wine bottle stoppers are devices used to seal opened bottles of wine, preserving the wine's freshness and flavor. They come in various materials, including cork, silicone, and metal, and are designed to fit snugly in the neck of the bottle. Proper sealing helps prevent oxidation, which can spoil the wine. Many wine enthusiasts prefer using stoppers over the original cork because they are often easier to use and can create a better seal. Some stoppers even feature vacuum mechanisms to remove air from the bottle, further extending the wine's shelf life. Popular brands include Vacuvin and Oxo.