Material: The silicone crown caps are made of BPA-free, food-grade silicone, specially designed for food. The lids are absolutely food safe, colorfast and odorless.^ Material: The silicone crown caps are made of BPA-free, food-grade silicone, specially designed for food. The lids are absolutely food safe, colorfast and odorless.^ Keep fresh: The silicone crown caps keep your drinks fresh for a long time and protect them from losing carbon dioxide. Airtight hygienic seal keeps your drink fresh and insects stay out. This keeps the drink fresh and tasty for longer.^ Marking surfaces: The silicone crown caps are available in many colors. The bright colors can distinguish the different bottles so that there is no confusion and each has its own color.^ Reusable: The silicone crown caps are easy to clean and suitable for many types of bottles such as mineral water, wine, champagne, soda, cola and other drinks.^