caspian 12, 18, 22 qt. blue square polycarbonate food storage container lid, 1 piece (12、18、22qt lid) caspian <p>it is specially designed for square food storage containers. use this lid to cover freshly sliced fruits, vegetables, sauces, soups, flour, etc. this lid is made of food grade and durable plastic material without bpa. and it has nsf certification listed which focus on food safety. in addition, it can provide a safe seal to prevent external contaminants from entering and excreting.</p>