Description How to use: Release button at the top. Stainless steel (surface), reinforced plastics (inner),and silicone. Fits standard wine bottle necks. Great necessity for wine storage. Vacuum pump removes air to halt oxidation process. Let you store wine after opening bottle. Keeps the open wine fresh for several days more. Apply to restaurants, hotels, bars, clubs, KTV, cafes.etc Description Material:Stainless steel (surface), reinforced plastics (inner),and silicone. Size: Approx. 5cm x 4.2cm x 4.2cm. Color:As pictures show. Package Included: 1 x Stainless Steel Wine Bottle Stopper. Description It can emit carbon dioxide for honey, white wine, milk wine alcohol fermentation and can prevent oxidation. Easy operation, simply fill water into the exhaust valve, insert it to the cover of the brew barrel or rubber plug on the top of the fermentation container and then cover it with the lid. Effectively prevents flies flying into the wine/beer with a cover included. All of the fermentation process is automatic fermentation without manual control and can be repeatedly used for a long time. Suitable for pure juice fermentation, such as white grapes, honey wine fermentation, red wine secondary fermentation, etc. Specification: Material: PP. Color: as pictures shown. Size: 17cm. Note: There might be a bit color distortions due to different computer resolutions. There might be a slight errors due to different hand measurement. Package included: 1* exhaust valve. _x000D_