NanoNine Micro Safe Steel Stainless Steel Single wall lunch box is designed to keep warm food fresh and retain aroma taste longer FOOD GRADE BPA FREE LID The Lid is made of Food Grade and BPA free plastic material Microwave Safe Containers Top three round containers are Microwave Safe and to be used without Lid AIR TIGHT The Air Tight lid of the lunch box keeps food fresh for hours HIGH QUALITY STAINLESS STEEL BODY Lunch Pack is made with Rust Free and Corrosion Resistant Stainless Steel