The Silicone Suction Sealing Lids are 100% Pure Food Grade Silicone. They are Dishwasher Safe and Microwavable, as well as Heat Resistant, Bendable, Odorless, and Non-Toxic.3 pieces of 6x6" Lid Set. The suction lids protect food quality and hygiene while safely storing food without environmental waste, protecting the longevity and quality of the food.Designed to fit nearly all sizes of bowls, cups and containers. Suction feature allows for an air tight seal on any smooth rimmed containers