The Charles Viancin lid is a beautiful and practical alternative to plastic film. Unlike plastic, these silicone lids can be reused over and over. The lid closes tightly on all smooth rims, meaning each bowl can be used for food storage. The sunflower lid creates an air and waterproof closure technology for warming up and storage. It can also be used while serving food to keep your food hot or cold longer. The lids are oven, microwave and heat resistant up to 500 degrees Fahrenheit.