The lunch box body is made of high quality 304 food grade stainless steel, LFGB certified and the lid is made of natural high quality bamboo, BPA and plastic free, non-toxic, reusable and more in line with sustainable environmental guidelines.The stainless steel has a fine and thick metallic character, combined with an environmentally friendly polishing process that is very comfortable to the hand, finally the outside of the box is finished with a matte finish to prevent external scratches and fingerprints.Support custom logo.