High-quality material: These stretchy cup lids are made of food-safe silicone, safe and healthy, can come into contact with food, non-toxic and environmentally friendly, reusable and durable. Temperature resistance: The silicone lid withstands temperatures from -40°C to 230°C, safe for dishwasher, microwave, freezer, and oven. Stretchy and durable: This cover for preserving bottles is made of premium silicone, flexible to fit different shapes of containers such as bowls, glasses, pots, and cups. Durable and reusable. Excellent airtightness: Airtight seal keeps food fresh for longer and protects against leaks. Both the lid and the edge of the container should be dry before attaching. The silicone stretch lid is better than plastic film. Multi sizes for multi-function: Stretchy silicone lids in 6 different sizes (diameter approx. 6.3 cm, 9.4 cm, 11.4 cm, 14.5 cm, 16.5 cm, 20.3 cm), suitable for most containers such as salad bowls, bowls, glasses, cans, cups, mason jars, pots, etc.