This Italian-made champagne stopper can withstand a pressure of 88 psi. It features a unique self-sealing design. By applying Pascal's Law, when the internal pressure of the bottle increases, the plastic stopper will expand outward to form a bubble seal. Regardless of whether the bottle is placed horizontally or vertically, the sealing effect is consistent. It can effectively lock in carbon dioxide, prevent the champagne from oxidizing, and maintain the bubble flavor. The product is free of BPA and phthalates. It is compatible with all standard 750 ml champagne and sparkling wine bottles. It can also be used for Prosecco, Cava, some 1.5-liter and 187 ml bottles, as well as various large bottles of beer, apple wine. When using, simply press down on the bottle cap and then lock it with a stainless steel safety clamp. The operation is simple and quick. Even arthritis patients can easily open and close it. After sealing, the bottle needs to be kept chilled to maintain the bubble flavor.