Silicone covers are a great way to save money when keeping your stored food fresh each cover is reusable and can be placed safely in a freezer or microwave due to the stretchy silicone material the covers can be used on any shape dish sealing perfectly features very stretchy suitable for containers of 15 24 cm freezer microwave and dishwasher friendly from 40 c to 230 c air and water tight with these covers you can seal containers airtight whether round square or oval