Description These wine bottle stoppers provide an air-tight seal to prolong and preserve opened bottles of wine. Designed to keep air out of bottle and slowing oxidation rates, keeping wine fresh. Made of premium material, safe, durable, easy to use and easy to clean. Feature - Color: As shown. - Material: plastic. - Size: About 18x5x2cm - Use the principle of water seal, which can effectively isolate the oxidation of fermentation medium by outside air. The whole fermentation process is automatic fermentation and exhaust at normal temperature, without manual control - Designed to keep air out of bottle and slowing oxidation rates, keeping wine fresh. - Just fill it with water and insert it in the opening and the bottle is sealed tightly. And remove it with a single pull. - Easy to use, simple operation, and can be reused for a long time. - Suitable for pure juice fermentation, such as white grapes, mead fermentation, secondary fermentation of red wine, etc. Use the principle of water seal, which can effectively isolate the oxidation of fermentation medium by outside air. The whole fermentation process is automatic fermentation and exhaust at normal temperature, without manual control Designed to keep air out of bottle and slowing oxidation rates, keeping wine fresh. Just fill it with water and insert it in the opening and the bottle is sealed tightly. And remove it with a single pull. Easy to use, simple operation, and can be reused for a long time. Suitable for pure juice fermentation, such as white grapes, mead fermentation, secondary fermentation of red wine, etc.