These round airtight food storage containers are amazing! Available in 10 different sizes, they will fill your every need. Once you try these, you won't want anything else. They are made from 18/8 food grade Stainless Steel, (The best of the best!) and the lid has a silicone seal. The containers are completely air tight. You can also write on the container with a non-permanent marker. This helps to specify the contents, date and owner. The bottom part of the container can be washed in the dishwasher, but the lid is not dishwasher or oven safe.