How Does It Work? Our sparkling wine stopper is more advanced than traditional stoppers. The seal is based on a simple yet effective physics principle (Pascal's Law). As pressure increases inside the bottle, the plastic nipple expands outward, forming a secure, airtight seal. Whether you store your bottle upright or flat, the seal performs consistently. BPA and Phthalate Free. Fits All Standard Bottle Necks The bottle shape does not matter - if the neck matches a standard 750ml Champagne or Sparkling Wine bottle neck, this Champagne preserver will fit. It works with Prosecco, Cava, some Magnum and 187ml bottles, as well as many large format beer or cider bottles. Easy To Use Unlike older Champagne bottle stopper designs (such as the spring-loaded type), our Champagne Saver is simple and quick to use. Just press the cap down (the seal does the rest), then secure with the stainless steel safety clip. It is easy to release, even for those with limited hand mobility. For best results, seal the bottle immediately after opening and keep it chilled.