Silicone Material: The product is made of food-grade silicone material, BPA-free, healthy and safe, with robustness, high temperature resistance, and a long service life. The silicone lid set comes in a total of 5 different sizes, meeting your diverse needs on different occasions and holding almost anything.Good Sealing & Anti-Dust: The silicone drinking glass lid adheres to the rim of the cup, is dustproof, and sealed. It can prevent liquids from spilling, even if the cup is tilted. To remove the glass lid, you can simply lift it from the side.How It Works: The way vacuum lids work is that you gently press in the center, and the lid creates an airtight, watertight, and leak-proof seal. You can then use them to store leftovers, food, salads, vegetables, pasta, soups, ingredients, etc. They're also ideal for cooking, keeping meals warm longer, storing food in the refrigerator or freezer, etc.Reusable and economical: These eco-friendly silicone lids are easy to clean and therefore reusable. Stretchable silicone lids replace cling film and aluminum foil, making them more environmentally friendly. More economical and more convenient.