Made of food grade stainless steel material, BPA free, stackable lunch box. Very health friendly! Separate compartments perfectly allocated according to your daily nutrition for your daily use. he elastic sealing ring and seal snap lid work together well to form an airtight and leakproof seal,don't worry about food spills. This bento food box can be used as a work lunch box, a bento box for children to go to school, a food container for outdoor spring trips, fall trips, camping, and park occasions.