SIX REUSABLE STRETCH FLEXI LIDS Six Reusable Stretch Lids are flexible, airtight design stretches to fit any oval, square, rectangular or round containers, sealing in freshness, extending life of food. Heat and cold resistant. Dishwasher, microwave and freezer safe. Includes three small 5" lids that stretch to 7" and three large 7" lids that stretch to 9". Silicone.