HIGH QUALITY lunch box is made of stainless steel and food grade PP material BPAfree healthy and durable We use thicker materials that are not easy to break The top and bottom are very strong DISHWASHER FREEZER SAFE This Stainless Steel tray is removable can be cleaned up easily in the dishwasher The plastic bottom box is freezer safe BPA free another useful function is you can pour in some hot water before you eat to heat the food LEAKPROOF The lid fits tightly to the stainless steel food tray so food does not run from one compartment to another preventing food from mixing With a 100 leakproof you can store liquids such as sauces or yogurt in it PORTION CONTROL 3 compartments Features convenient to store variety food with divided lunch box design portioned perfectly for adult childs appetite durable and easy togo Thermal Technology The builtin water injection feature makes it easy to heat or cool Simply add hot or cold water into the bottom basin before breakfast lunch or dinner The bottom bowl is made of food grade PP and can also be used to hold fruits or salads The lunch box itself does not have a longterm heat preservation effect it needs to be added with hot water to achieve heat preservation and the heat preservation time is about 1 hour