Each bowl comes with an airtight silicone lid, enabling you to prep ingredients in advance and keep sealed so they are fresh and ready to use when you need them. The Viking 10-piece Stainless Steel Bowl Set can be nested for compact and easy storage when not in use. The bowls are refrigerator and freezer safe for short-term food storage as well. Both the bowls and lids are dishwasher safe (top shelf only for the lids). Viking recommends hand-washing to extend the life of the silicone and shiny finish of the bowls.Viking 10-Piece Stainless Steel Mixing, Prep and Serving Bowl Set in Black