Keep your pet's canned food fresh after opening. These canned-food lids are self-sealing, flexible, and allow you to keep pet food fresh without ever having to transfer it from the can to another container. Simply place the lid over the can, and press down in the center of the lid to create a vacuum seal. Pull up the edge to break the suction and remove the lid. These lids are simple to clean as well -- just pop them in the dishwasher.