Suitable size: Our wine stopper is suitable for most flat-mouth red wine bottles (inner diameter 18-19 mm) / champagne (inner diameter 17.5-18 mm). It is not suitable if the wine bottle mouth has a thread. We recommend that you pay attention to whether the size of the wine/champagne stopper is suitable for your bottle before purchasing. Keep the wine fresh: The wine bottle stopper has good airtightness, can remove the air in the wine bottle and minimize the oxidation of the wine by sucking the air out of the bottle. Fit the wine cork more tightly to the bottle, seal the gas tightly in the bottle, prevent bubbles from slowly dissipating after opening the bottle, and keep the wine fresh for up to 7 days. Twist-lock design and easy to use: Equipped with a twist-lock design, simply twist the top of the champagne bottle stopper to the locked position to completely lock the vacuum wine stopper to the bottle neck, and your champagne/wine will be well sealed. This is simpler and easier to use. High-quality materials: The interior of the wine preserver vacuum is made of food-grade silicone material, and the exterior is made of food-grade ABS, which ensures the safety and durability of the champagne bottle stoppers. The appearance is simple and stylish, the volume is small and exquisite, and it is easier to store.