Material: The interior is made of high-quality SUS 304 stainless steel, designed to be durable, hygienic, and rust-resistant.Design: Each lunch box features a multi-compartment layout to separate different types of food and prevent mixing of flavors.Features: They are designed with airtight locking clips on the sides to keep food fresh and prevent leaks.Included Accessory: Each container comes with a matching blue spoon for eating.